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fvfdrums
18-05-2012, 05:51 PM
I have been lurking around on the site for quite some time now reading all the build logs for various sized machines and the advice people have been offering and it has been extremely eye opening and has change my plans of what I have wanted to build several times over I am finally at a stage where I beleiev I have a reasonable budget to not be scrimping on parts to build something half decent and with the advice of others I can only imagine it will get better!

a bit of background.....

...... my previous experience with CNC was with a 3 axis chruchill matrix cnc lathe which was an enormous beast in comparison with what I am intending to build. I want the machine to be capable of machine hardwoods, aluminium, plastics etc at a reasonable DOC, the mill is not for one specific task as it were as I am always up to all sorts so it needs to be big enough to allow for a wide variety of parts to be made but I am limited in space so it really cant be too big.

Current thinking :

Rough dimensions: 120 x 800 table size

Steel box section construction

2.2kw chinese spindle

x\y running on fully supported rails, z on hiwin profile rails

16mm ball screw (twin drive x axis) singles on y and z

Potential for manual adjustable bed height (bolts out move it bolts back in)


At the moment I am working away in solidworks to develop the design a bit further before sticking it up on here but I thought I would air a few ideas first incase I need to make some changes straight away.


My main issue at the moment is to do with the fully supported rails vs the hiwin style bearings. I know this is always the case and a lot of the deciding factor can be down to cost which is not the only reason for asking this as if I can find a way to use them I will do.

First off making a machine of this size, what size rail would I need in terms of the hiwin rails bearing in mind the main gantry will be a large piece of steel box section at the moment.

I know some peoples opinions of the open ended bearings are that they are terrible, other than using hiwin is there anyway to make them any better? using more carraiges under the gantry 3 per side? 2 above 2 below connected by a plate on the x axis as you would do on the y axis so the openings are opposed?

I would like this machine to be pretty accurate if I am going to the effort of investing time and into it and am I going to be utterly dissapointed with these linear bearings over the profile rails.

Thanks for reading and I hope this thread will come togther to form an interesting build once I get going soon.

Cheers

Francis

Jonathan
18-05-2012, 06:23 PM
Rough dimensions: 120 x 800 table size


Typo surely, 1200mm? Rest of my post is based on the assumption that it is 1200*800. What Z-travel?

Since you want to machine 'aluminium at a reasonable DOC' then an adjustable height bed, or very small Z-travel is critical. Clearly a small Z-travel is quite limiting for machining non-metals, so the adjustable height bed is preferable.

You should be able to get the profile rails on eBay for a good price - certainly a lot less than new. 15mm rails will be good compared to any size supported round rail since it is the pre-load that makes the profile rails more rigid. If you find bigger (20-25mm) rails then that's good, but it's not worth spending a lot more on them. Since you seem to have waited 5 years to post I guess waiting a bit longer for the right price isn't a problem!

You could try 4 rails on X as you suggested, I considered it for my machine. The problem with the supported round rails is that the bearing blocks are not preloaded, so even though load ratings are plenty high enough adding more bearings doesn't magically pre-load them so it will still be worse.

fvfdrums
18-05-2012, 06:43 PM
Jonathan,

Thanks for the response, yes it was a typo 1200 is correct. I am not sure on the z travel at the moment I am looking to keep it reasonably short this was the reason for the adjustable bed. What would you consider a reasonable z travel based on machining aluminium?

So I could go as small as 15mm ok that helps I was expecting to need 20mm dont ask me why just thought that would be more the size.

I see you use those bearings on your machine, by saying they will still be worse than the profile rails what exactly am I likely to notice between using the two? (thats not me posing that questions as if im not expecting the profile to be better because I am just wanted to know what key differences in the machined end product)

JAZZCNC
18-05-2012, 06:46 PM
If you have been lurking long enough you will have probably seen my dislike of round rail/bearings and complete louthing of unsupported rail.!! . . IMO really is no comparison between round rail and profile rail.! Profile rail makes the difference between DIY machine and Pro machine that will out last the machine and out perform round rail by magnitude of 10X.

To me if your serious enough to invest couple of grand and several months of hard graft then the extra cost is just not worth skimping on and like Jonathan says if you've waited 5yrs then don't spoil the broth for a pinch of salt and wait untill you can afford them.

Regards size then 15mm will more than handle the load but I find 20mm is the better option due to bearing size being slightly larger offering better support and easier mounting. 25mm is just over kill unless really large/heavy machine and waste of money plus has well has being inefficeint and stressing the motors more.

fvfdrums
18-05-2012, 06:58 PM
Jazz,

To be fair I expected that comment and yes I do agree that profile is the way to go just got to find a good supplier!

Any suggestions?

Jonathan
18-05-2012, 08:54 PM
just got to find a good supplier!
Any suggestions?

eBay is by far the cheapest place. Unsurprisingly shorter rails are more common so you may have to wait a while to find rails for the X-axis, but it's clearly worth it.

routercnc
18-05-2012, 10:17 PM
Hi fvfdrums,

When I made my machine a few years ago I bought profile rails from this place on ebay. For example:
http://www.ebay.co.uk/itm/THK-SSR20-Linear-bearings-rails-L780mm-cnc-nsk-router-block-/280871641003?pt=LH_DefaultDomain_0&hash=item4165411fab

They are second hand parts, so you take a chance, but I ordered a pair at 700mm (Y) and a pair at 300mm (Z). 700mm was about 140 for pair of rails and 4 blocks, and 300mm was around 80 for pair of rails and 4 blocks. Vaguely remember paying import tax on one of these orders. They had a very smooth action and work very well on my machine although I only really cut plywood, liteply, and balsa.

fvfdrums
19-05-2012, 10:38 AM
Routercnc, thanks for the link I will keep an eye out for something that fits the build. Did you find them to be a good seller? How long did they take to arrive?

After sleeping on it I am 100% behind profile rails so am going to hunt some down.

I will get the design outlay up over the next few days and let the critics at it!

JAZZCNC
19-05-2012, 11:50 AM
Many moons ago I bought a class 1 ballscrew from the same guy routercnc suggested and was very happy with it, still are.! Thou it did need a strip down and clean to be fair so be prepared that you may have to get slightly dirty to get best from a used components.
Still it's a good cheaper way to have profiled rails and worth the effort and risk. Even if there's a bit of play or slop then it's not difficult to replace balls in both bearings or ballscrews so they can be brought back to life or certainly far better operation.

If I remember correct they didn't take long to come roughly about 2-3wks and was packaged ok.

fvfdrums
19-05-2012, 12:14 PM
Thanks for that Jazz,

I was looking at the prices on there and to be honest by the time I have added up the cost of shipping the lengths I am looking at and added the chance of VAT on top its looks like I could buy the same from Zapp for about 25 more but new (thats based on what they have on their eBay store at the moment) probably better to go new I would have thought.

I am assuming 4 blocks on the z axis is a must for a machine like this? This was the original plan but i thought i better check.

JAZZCNC
19-05-2012, 01:05 PM
check your PMs

Jonathan
19-05-2012, 02:35 PM
I was looking at the prices on there and to be honest by the time I have added up the cost of shipping the lengths I am looking at and added the chance of VAT on top its looks like I could buy the same from Zapp for about 25 more but new (thats based on what they have on their eBay store at the moment) probably better to go new I would have thought.

I am assuming 4 blocks on the z axis is a must for a machine like this? This was the original plan but i thought i better check.

Definitely 4 blocks. The problem is you're just looking at buyitnow listing, which are obviously going to be more expensive than waiting and bidding. Via bidding and negotiation my friend and I have got the following:

Hiwin: New, Two rails and 4 blocks, 15mm*640, 80
Hiwin: New, Two 15*760mm Two 15*1150mm, 10 blocks, 360

THK: New, Two rails and 4 blocks, 25mm*760mm, 100
THK: Used, Two rails and 4 blocks, 25mm*300mm, 80

...etc, you just have to be patient and I need to stop buying them all!

All of those prices are significantly less than the eBay listing linked to in post #7... than one isn't a good deal.

I still want to get two 2120mm rails for my X-axis, but ones that long don't come up very often at all and postage is of course very expensive.

JAZZCNC
19-05-2012, 02:46 PM
Hiwin: New, Two rails and 4 blocks, 15mm*640, 80
Hiwin: New, Two 15*760mmw Two 15*1150mm, 10 blocks, 360

Probably Stolen goods. . Lol

Jonathan
19-05-2012, 02:52 PM
Forgot to mention, those are all rails/blocks with 4 rows of balls which is what you want since their load rating is equal in all directions and the moment load is greater. Two rows is still fine if they're quite big and clearly still far superior to supported round rails.


Probably Stolen goods. . Lol

I better keep them locked up else they will be!

JAZZCNC
19-05-2012, 02:59 PM
Forgot to mention, those are all rails/blocks with 4 rows of balls which is what you want since their load rating is equal in all directions and the moment load is greater. Two rows is still fine if they're quite big and clearly still far superior to supported round rails.

I very rarely see 2 row bearings for sale.! Where do you see them.?


I better keep them locked up else they will be!

Better still get them working and earning there keep.!!

routercnc
20-05-2012, 07:50 AM
I found them to be a good seller. About 3 weeks to arrive and reasonably packaged in a thick cardboard board with lots of bubble wrap. Would buy again if building another machine (!). My parts were clean and ready to use.

For info I see alot of machines using supported rail on the Z axis and whilst there is nothing wrong with that I would recommend new builders (or upgraders) to have a look at these used profile rails. Putting aside all the advantages of profile rail, their compact size makes for a neat installation in an area of the machine that benefits from compactness. And these short lengths (typically 300mm in a 15mm width) make it good value at about 80 all in.

I know what you are saying about the longer lengths. For my X axis (1300mm) I went with new supported rail from linearmotionbearings2008 (ebay).

Since the Z axis always has an unavoidable overhang I would personally go for 4 blocks.

fvfdrums
20-05-2012, 10:02 AM
Ok I'm going with profile rails on all x,y & z 4 blocks on each rail.

My thoughts are going towards a low level gantry eg minimum deflection in relation to the x axis with the adjustability of the bed. I have access to a fair bit of 100mmx100mm off cuts and was thinking of using this as the base for the machine. Would this be too extreme for the gantry?

Jonathan
20-05-2012, 02:19 PM
My thoughts are going towards a low level gantry eg minimum deflection in relation to the x axis with the adjustability of the bed. I have access to a fair bit of 100mmx100mm off cuts and was thinking of using this as the base for the machine. Would this be too extreme for the gantry?

Excellent. Nothing's too extreme. The worst that will happen is you might need bigger motors, or have to accept lower feedrates (which is irrelevant for aluminium cutting). Design the machine then select the electrics to suit. Don't start trying to make things lighter to optimise the feedrate since a rigid slower machine is much better than a fast weak one.

JAZZCNC
20-05-2012, 03:23 PM
Excellent. Nothing's too extreme.

Design the machine then select the electrics to suit.

Completely 100% agree on both counts. . . . If you then filled it with concrete you still wouldn't be extreme, Infact if you mainly intend cutting Aluminium I recommend you do exactly that has it makes a big difference to resonance and quality of finish.!!

fvfdrums
20-05-2012, 05:46 PM
Right I have had an hour to play in solidworks so this is not very detailed its just an outline of the idea I am thinking of once I have ironed out any potential problems I will go in a bit more detail.

So once again 1200mm x 800mm bed current z axis 200mm ? good bad ugly?

z axis is based on 4 blocks sitting on a 200mm square footprint eg one on each corner of a 200mm square.

Adjustable bed for altering depths of material / things to machine.

twin ballscrew on the x axis, single on the y and z

concrete/ sand etc in the box section taken on board I will give that a go.

60166017

JAZZCNC
20-05-2012, 11:07 PM
concrete/ sand etc in the box section taken on board I will give that a go.

Ah so you've seen me mention sand before.!! Yes dry kiln sand works good and is easily removed.

Like the chunky frame look forward to the detailed version.!

Jonathan
21-05-2012, 12:05 AM
Ah so you've seen me mention sand before.!! Yes dry kiln sand works good and is easily removed.

That or seen someone else mention it - it's a well documented solution.

I'd go for epoxy granite over concrete. Concrete moves/warps after it's set and since you're using profile rails any movement in the piece they're mounted to could cause serious problems. If the rail is bent ever so slightly the slide coefficient of friction increases dramatically, so if this happens over a long period of time you probably wont notice until the machine stalls due to the greater power needed to move each slide. By that point some serious wear could have occurred to various parts in the system.

Frame looks appropriately sturdy, but I'd be inclined to add some smaller box section to link the legs. It wont cost much compared to the rest of the frame and could help with resonance, since at the moment you have a large mass supported by legs (rather like a cow which wobbles a lot if you push it!)

JAZZCNC
21-05-2012, 12:21 AM
That or seen someone else mention it - it's a well documented solution.

I'd go for epoxy granite over concrete.

Ye but seemed logical has I mentioned concrete and he added sand which I've mentioned and recommended many times in the past.!! . . . . But does it matter.!!

Personally I wouldn't go with Epoxy or concrete.!! Sand is cheap the concrete example was to make a point that heavy or dense is good.!
Epoxy is not a good solution either has the heat from the large qty of epoxy could and will warp the steel.!! . . .Plus the cost of epoxy it would be just has cheap to buy plate steel.??

fvfdrums
21-05-2012, 01:34 AM
Sands good with me likely hood is I'll need to move the machine at some point so the potential to "drain" some weight would be useful

Jonathan
21-05-2012, 02:03 AM
Personally I wouldn't go with Epoxy or concrete.!! Sand is cheap the concrete example was to make a point that heavy or dense is good.!

Yes of course, sand is perfect going by the 'heavy is good' and reducing resonance arguments. However it doesn't add strength, unlike concrete/epoxy. I assumed you suggested concrete additionally for that reason. It's a shame the cost of epoxy is so prohibitive.

John S
21-05-2012, 09:42 AM
It's not prohibitive, you just want everything for nothing.

JAZZCNC
21-05-2012, 06:46 PM
I assumed you suggested concrete additionally for that reason. It's a shame the cost of epoxy is so prohibitive.

There you go again with your ASS -Sume-ing.!!

fvfdrums
23-05-2012, 10:31 AM
Ok, I think I have decided I am going with the twin ball screws on the X controlled by one motors running a belt drive system for the two drives. As much as i think it might be easier to implement the motors to start with the idea of not having to "tune" the motors to work together appeals greatly.

JAZZCNC
23-05-2012, 01:52 PM
Ok, I think I have decided I am going with the twin ball screws on the X controlled by one motors running a belt drive system for the two drives. As much as i think it might be easier to implement the motors to start with the idea of not having to "tune" the motors to work together appeals greatly.

Wise choice and won't regret I know that.!

fvfdrums
16-12-2012, 10:29 AM
Right,

Been quite a while since I was posting about this but it is still going ahead, albeit "general life" has got in the way as it does with so many projects but I now have a Friend on board so we are splitting the costings 50/50 so we have a realistic budget to work with and hopefully the specs are adding up now. Still got a few questions really.

Here is the current spec:

1200x900 footprint area with approx 1000 x 800 cutting area
80x40x4mm steel box section frame with adjustable bed
Aluminium gantry made from a combination of 20mm/15mm plate either standard 6082 or ecocast for the bearing and guide plates
20mm Profile rail on x,y,z
20/05 on x axis (running 2:1)
16/10 on y axis
16/05 on z axis
250mm cutting depth on z
2.2kw chinese spindle

electronics (just ideas at the moment)

1 x nema 34 7.7nm running 2 x axis ball screws via a timing belt (as suggested by JAZZ) running 20/05 screw on a 2:1 ratio
1 x nema 23 3.1nm running y axis on 16/10 screw
1 x nema 23 3.1nm running y axis on 16/05 screw for better resolution

80v Chinese Drives

80v PSU

Mach 3

Price wise everything has been accounted for in our budget which is great managed to get some really good prices on steel and aluminium. I have a couple of questions which as I know may not be possible to answer without imagery but I thought I would pose them anyway!

The length of the x axis thread is 1200mm would this run with 16/10? or is it better to just stick with the 20/05 to prevent the chance of whipping as I was under the impression thats getting to the limit or even past what it should before it whips?

Running the X off a nema 34 and the y and z off nema 23s, would this pose any sort of problems with setting the machine up? is it better to have 34 all round as I am quite happy to do this as all of the screws are belt driven in some form so adjusting the gear ratio to compensate for slower rpm is not a problem. The machine is still being designed to cut aluminium primarily and then hardwoods

The current weight of the gantry based on calculations of size and weight including aluminium, bolts to assemble, spindle, rails and carraiges, Stepper motors and any other parts that were per the design is in the 65-68kg range.

We are hoping to get started on this in early feb and to have a moving machine by the end of march, thats not a completely finished machine but one that can move, even if we have to push it!

JAZZCNC
16-12-2012, 11:23 AM
1 x nema 34 7.7nm running 2 x axis ball screws via a timing belt (as suggested by JAZZ) running 20/05 screw on a 2:1 ratio
1 x nema 23 3.1nm running y axis on 16/10 screw
1 x nema 23 3.1nm running y axis on 16/05 screw for better resolution


Hold on think we may be at cross purpose's here or I've miss under stood you.? I wouldn't have recommended those screws and motors at this size.? Longer yes but not at 1200mm.

16/10 and 3.1Nm 23's will be much better.

Edit: The only exception is if you want to link the screws with timing belt.? Then you'll need the bigger motors but 16/10 could still be used.?
Also don't use 80VPSU with 80V drive. You need a safety net for back EMF so use 75V psu with 80V drives.

fvfdrums
16-12-2012, 11:39 AM
Hold on think we may be at cross purpose's here or I've miss under stood you.? I wouldn't have recommended those screws and motors at this size.? Longer yes but not at 1200mm.

16/10 and 3.1Nm 23's will be much better.

Edit: The only exception is if you want to link the screws with timing belt.? Then you'll need the bigger motors but 16/10 could still be used.?
Also don't use 80VPSU with 80V drive. You need a safety net for back EMF so use 75V psu with 80V drives.

My fault I am sure, the x axis will be joined with a timing belt in which case would this still negate the 34 or would the 23 be adequate. but if I can use the 16/10 then thats great!

Noted on the drives voltage that makes sense must be a sunday thing on my part! As ever cheers for the response!

JAZZCNC
16-12-2012, 12:26 PM
Has sent FVF via email regarding others stuff has well as this but posted for benefit of others and to keep the thread complete without back door dealings so to speak. . .Lol


Seeing your post got me wondering if i'd cocked up on advise but on reading this email again I feel vindicated and relief . .. Lol

To be honest I didn't realise or missed the length was only 1200mm.
Given this then it will be better to use 16/10 has it gives more options. If your wanting to still only use 1 motor linked with belts but nema 23 motor then there's still a possible option.? Thou i've never done it but can't see any problems if only cutting at lower feed rates needed for aluminium.!

Like using the 34's gear it but in reverse so 2:1 (2x turns motor 1x screw) this has the affect of doubling the torque and increasing the resolution at the sacrifice of speed.

To be honest with the price of digital drives dropping significantly and the fact they are soooo much better than Analogue drives in general but esp at handling stalling. Being able to stop all motors when one motor is detected Stalling has meant the racking issues when using twin slaved motors is greatly relieved and with minimal risk of damage if happening at high feed rates.

That said your if your mainly going to cut aluminium then slaved motors is not so much a risk has again the feeds are low so available torque higher. Esp if geared 2:1

Hope this helps
Cheers
Dean.

PS: I will post this on the forum for others to see and critique.!!

Jonathan
16-12-2012, 01:12 PM
Agree with jazz about the X-screw - RM2005 wont help. The problem is the pitch is half what you get with RM1610, so you have to spin the screw twice as fast to get a given feedrate. Going from 16mm diameter to 20mm doesn't make the critical speed twice as much (only 25% more) so you actually end up worse.

RM1610, critical speed - 1460rpm => 1460*10=14.6m/min
RM2005, critical speed - 1825rpm => 1825*5=9.1m/min

The feedrate with either screw is plenty, but since 20mm is more expensive and in addition to the above a 20mm screw requires significantly more torque than 16mm, so you only gain stiffness/lifetime which on a router like is completely negligible since the 16mm screw is strong enough and will last for many years.

fvfdrums
16-12-2012, 01:24 PM
Jazz & Jonathan

As ever thanks for the informative responses

I follow on the 16 thread thats fine...... so I guess now really its a case of deciding between one motor driving two screws or having them slaved?

Based on the spec what would you guys do if it were you? And will 1 x 23nema 3.1nm running both x axis screws be man enough?!? or is it better to just go down the twin motor route?

fvfdrums
17-12-2012, 07:55 PM
Updated spec after current discussions:

1200x900 footprint area with approx 1000 x 800 cutting area
80x40x4mm steel box section frame with adjustable bed
Aluminium gantry made from a combination of 20mm/15mm plate either standard 6082 or ecocast for the bearing and guide plates
20mm Profile rail on x,y,z
**16/10 on x axis (running 2:1)**
16/10 on y axis
16/05 on z axis
250mm cutting depth on z
2.2kw chinese spindle

electronics (just ideas at the moment)

1 x nema 34 7.7nm running 2 x axis ball screws via a timing belt running dual 16/10 screws
1 x nema 23 3.1nm running y axis on 16/10 screw
1 x nema 23 3.1nm running y axis on 16/05 screw for better resolution

80v Leadshine Drives

75v PSU

Mach 3

How is this all sounding? are we on the right track :)

Design wise the gantry design is very similar to the one Jazz has posted on here before with interlocking aluminium plates (copying someones idea is the best form of flattery right? or is that plagiarism :P) anyway it looks an extremely solid design and I tend to make things over engineered so figured this was a good place to start.

With the y axis I was considering a direct drive using a coupler, all the other drives will use a belt to transmit motion, would it better to engineer it so the motors are all belt driven or would this make no odds?

JAZZCNC
17-12-2012, 08:19 PM
**16/10 on x axis (running 2:1)**

1 x nema 34 7.7nm running 2 x axis ball screws via a timing belt running dual 16/10 screws


This contradicts the other.? If using 10mm pitch you won't need any ratio with 7.7Nm 34 and belt drive 1:1 will be fine.




With the y axis I was considering a direct drive using a coupler, all the other drives will use a belt to transmit motion, would it better to engineer it so the motors are all belt driven or would this make no odds?

No don't direct drive keep the belts for resonance reasons even thou your planning using very good drives which handle resonance fantastic. If your copying the gantry I think then I've actually changed the design slightly and the Motor is now on the inside connected to screw with belt. It's very neat and compact. (code for F@#% tight fit.!!)

fvfdrums
17-12-2012, 08:21 PM
copy and paste mistake yes I mean 1:1!!

I was looking into that possibility and I think I must have guess the dims pretty close as I had exactly the same design issues but I think I can get it in!

fvfdrums
18-12-2012, 10:53 AM
after a bit of redrawing last night I had a thought that the fk/ff bearings (which I have just stumbled across) may be a better option for the x axis that the bk/bf ones. I am trying to determine the exact length of the ballscrew I need and cannot tell if the bearings in these units are flush to the back of the mounting plates or they are set in? does anyone have or know a link to some accurate tech specs for these bearings? Because the design of the axis uses a plate either end of the frame to sandwich the x axis ballscrew between two bearing units and I need to know the length of ballscrew I need to order otherwise there will be play or it will be over sized!

Alternatively if I were to machine up my own bearing blocks for the x axis, the floating end is straight forward, what does the fixed end comprise of? angluar contact bearings? sizes?

D.C.
19-12-2012, 04:47 AM
Price wise everything has been accounted for in our budget which is great managed to get some really good prices on steel and aluminium.

I am going through the same design/collect materials phase that you are and I'm building a similar sized 2.2kw spindle, steel frame as you. In your budget did you account for all the 'little things'?

Like:

Control Cable
E-Stop button
Limit switches
Nuts & bolts
Water pump for the spindle
Tubing for the water pump
Connectors for the tubing
Cable runs
Welding supplies
Paint
Etc...

Accounting for all these sorts of things is adding an easy 200-300 to my budget (even with making my own cable runs after the machine is built) and then of course before I cut a single thing I'll need a few different router bits so that is another 50.

fvfdrums
19-12-2012, 09:41 AM
D.c

Thanks

Yes have accounted for around 450.00 worth of "finishing" as it's titled in our budget all those bits really add up I guess I am quite fortunate to have a fair amount of bits "in stock" also cutters and collets included from running a large cnc lathe previous to this but your right it's surprising how it all adds up!

fvfdrums
07-01-2013, 09:34 PM
Ok right I have hit the new year running so have a full months work of build time allocated between work over Feb and Mar. Now I have the dreaded tax return out the way I have the rest of this week to work on finalising the design etc whilst I am doing this I would like to try and figure out the best place to source things other than what I already know so if people in the know would not mind chiming in to let me know where they have bought the following from eg reputable suppliers:

Nema 34 & 23 steppers ?? chinese supplier?

Leadshine Drivers ?? chinese supplier wont be ordering these until the machine is mechanically together but would be good to know

2.2kw Chinese spindle ??

Steel Box section 80x40 ideally any good suppliers?

Alumimnium plate I will be getting from aluminium warehouse as this seems the best place for cut to size pieces

Ball screws and lead screws and bearing holders from Chai

Timing Pulleys from Bearing station or bearing boys

Any help with this list would be greatly appreciated, apologies if there is a thread with all this on I have just not come across it as yet

Cheers

Francis

kingcreaky
07-01-2013, 10:33 PM
Il help with the bits I can,
I used Aluminium Supplier | Aluminium Stock | Aluminium Warehouse (http://www.aluminiumwarehouse.co.uk/) for ali. I did a bit of a hunt and these lot where about as cheap as anywhere else and very convenient.
I also used and have been very pleased with chai.
One thing I will say though, is the BK bearing block for the RM16x ballscrews I bought seem to be very good. However the BF bearing housing seems rather poor. Fortunately, for my two long X ballscrews, I opted to have the screws machined at both ends, and use BK at either end. If I did it again I would also do the same for the Y ballscrew and Z Ballscrew.

timing pulleys, i used htd 15mm from Bearing Station - Adhesives, Bearings, Belts, Chains, O Rings, Oil Seals, Pulleys & Sprockets (http://www.bearingstation.co.uk/)

D.C.
08-01-2013, 10:22 AM
For the steel if you want online try fhbrundle:

Rectangular Hollow Steel Sections - F H Brundle (http://www.fhbrundle.co.uk/groups/30SHS__RHS)

For the aluminium either aluminium warehouse that kingcreaky already pointed out or ascmetals.
Metal Stockists: ASC Metals Lincoln Ltd. - Metal stockholders for East Midlands/North of England (http://www.ascmetals.com/contact.html)

It is worth phoning around a few local metal suppliers to see what is available from actual people rather than online it might work out cheaper especially if you can collect it.

For the motors I was planning on ordering from cnc4you, the price seems as good as ordering from china surprisingly... Unless anyone has found anywhere better of course.

Nema23 3.1Nm (http://www.cnc4you.co.uk/index.php?route=product/category&path=20_26)

The spindle/vfd off ebay, I think a few people have used solar.jean

kingcreaky
08-01-2013, 11:08 AM
Whoever you use, Id recommend getting all of your electronics from one supplier.

Although I got my steppers from cnc4you also, Zapp Automation Ltd (http://www.zappautomation.co.uk/en/) is a site sponsor, and from what I read a member on here and a very good at providing advice and support to the products you buy from him. No slight on cnc4you but if I did it again id use zapp for the motors / electronics as I suspect this area will trip me up most when I come to assemble it. as ive used an array of suppliers I suspect this may cause me a headache when asking support questions.

fvfdrums
08-01-2013, 11:27 AM
Thanks for the replies so far thats a great help, to be honest they are all names that have crossed my path before but its reassuring to find people whohave good experiences using them so thank you :)

Quick question Kingcreaky regarding the machining of the leadscrews I was considering doing the same think about having both ends machined but using the fk bearing supports the only problem I have is that I cannot work out from chais drawings when assembled does the leadscrew actually make contact with the face of the bearing within the housing or does it butt up against the seal outside? or is the seal wide enough to accomodate the machined portion of the screw through it ?

I figure a drawing may help here to explain what I mean if I get a load of ?????? coming back :)

kingcreaky
08-01-2013, 12:26 PM
Sounds like the very same question I spent best part of a day trying to work out, then Jonathon helped me :D

this is what you are looking for (I think)
7902

So, for me I wanted both ends machined to fit the BK style block. I wanted 1500mm of actual screw. First off, I required type A machining at both ends and I also wanted to drive the screw via a pulley so required dimension F to be slightly longer. so I order 2 of these for the X

** (1603mm Total length) I need (1500mm) of screw, so 1500mm PLUS one end machined to type A (except dimension F to be 25mm instead of 15, and the other end machined again to type A, but without any F


when they actually arrived they are more like 1606mm. (I think this is because in china they have more space for each mm :stupid: or their tape measures are backwards or something. perhaps the marks on the tape measure have to be slightly further apart to faciliate for the funny letters they use? PMSL

fvfdrums
08-01-2013, 01:07 PM
So am I right in thinking that where the screw ends and the machining begins is where it butts up against the bearing inside the housing?

Or put simpler if I ordered 1200mm of screwthread (plus the machining) with the bk attached at both ends I would have 1200mm of screw between the faces of the bk blocks?

I have just redesigned how I am mounting these as to start with I had fixed plates to hold the FK version bearings but was a little concerened that if I order this screw and find its even 3mm oversize length on the machining it wont fit so by going back to the bk style I have a bit more flexibility.

fvfdrums
08-01-2013, 01:18 PM
right ignore the last bit I think I have figured it out, is there a small spacer that goes in the bearing block?

kingcreaky
08-01-2013, 01:26 PM
Sorry, gonna have to pass on this question in the hope somebody else can reply. Until I get home and have a look atleast. I havent really inspected them. However, I think the bearing buts up against where the screw starts... no spacer.

fvfdrums
08-01-2013, 01:34 PM
I think I am beginning to confuse myself here! thanks for the help though.

fvfdrums
09-01-2013, 11:20 AM
Ok So after re drawing this gantry for what seems like forever to make it work the way I want I have nearly got it where I want it I think.

As said before this machine is heavily influenced by the red machine Jazz put up, so its all aluminium plate bolted together using ecocast plate where needed running on 20mm profile rails.

fvfdrums
10-01-2013, 07:51 PM
Ok can anyone recommend anywhere for the following?

Nema 34 approx 6nm and nema 23 3nm both from the same supplier? I can only find nema 23 from CNC4you

Also best place to get the dq860ma drivers?

Finally anyone had any experience with these guys?

PERFECT FOR NUMERICAL ENGRAVING/MILLING WATER-COOLED SPINDLE MOTOR 2.2KW q4 | eBay (http://www.ebay.co.uk/itm/PERFECT-FOR-NUMERICAL-ENGRAVING-MILLING-WATER-COOLED-SPINDLE-MOTOR-2-2KW-q4-/370565039081?pt=UK_BOI_Industrial_Automation_Contr ol_ET&hash=item564765c3e9)

Just noticed that they do a 34 at cnc4you but its an 8.7nm motor will this run with the above drivers ok. any alternatives for this motor more like 6nm? only thinking it might be a bit cheaper!

MikeyC38
25-03-2013, 11:13 PM
Hi Fvfdrums

I contacted a couple of people who had bought from happykissoul and they said they were happy with the quality and delivery though I've noticed that the price for a 2.2kw spindle + vfd on ebay has jumped massively from around 250 to nearly 650!!! :blue:anybody got any ideas why? - I'm about to restart my project :joyous:

Regards
Mike

PAULRO
02-04-2013, 10:25 PM
Hi FVFDRUMS, i have been watching this build log because i,m going to build a m/c similar to yours, similar cutting area with similar size tooling(20mm linear guides and 16mm ball screws) .the lengths will be different sizes. i plan to m/c hardwood ( the occasional guitar body) can you let me know where you bought the slides, ball screws and bearing blocks to suit? also is there a download of the specs available so i can incorporate this info in to my dwg.
By the way, how is your build going?

GEOFFREY
02-04-2013, 10:45 PM
Mike, I read another post that said the reason for the price hike is because none are available in the UK, but when back in stock the prices will be back to normal. G.

MikeyC38
05-04-2013, 12:23 AM
Hi FVFDRUMS, i have been watching this build log because i,m going to build a m/c similar to yours, similar cutting area with similar size tooling(20mm linear guides and 16mm ball screws) .the lengths will be different sizes. i plan to m/c hardwood ( the occasional guitar body) can you let me know where you bought the slides, ball screws and bearing blocks to suit? also is there a download of the specs available so i can incorporate this info in to my dwg.
By the way, how is your build going?

Hi PauRO

I got my parts from Chai at linearbearings2008 on eBay. Many on this forum have used him with good results. I got the following (see link) but swapped the supported round 1100mm SBR16 slides for SBR20. Chai was excellent in changing the order and I received everything intact within 10 days. 3 SBR16 sets +3 ballscrews RM1605+3BK/BF12 +3 couplers | eBay (http://www.ebay.co.uk/itm/3-SBR16-sets-3-ballscrews-RM1605-3BK-BF12-3-couplers-/250476169366?pt=LH_DefaultDomain_0&hash=item3a518b0896) . I'm building my CNC to make guitar bodies

Regards
Mike

fvfdrums
23-09-2013, 07:45 PM
Well its been quite a while (9months) since I was last on this thread talking about the machine I was about to start and as per usual a whole load of "Life" has got in the way preventing this from moving forward in the way I had hoped.

Anyway to cut a long story short its got to the time of the year when for me work goes a bit quiet and means I can legitimately take some "time off " a real rare thing, so I have now planned in for work to start on the machine in the 1st or 2nd week of November.

I now have a great garage space I have converted with heating and all my machine tools so it will be much easier to produce a better quality machine in the space.

Only problem is somehow in the last 9 months the folder containing all my drawings has vanished and apparently its nothing to do with the other half :| so I need to start drawing up from scratch again which will give me an oppertunity to have a look at the design with fresh eyes. Honestly I am not sure I will change too much from before as it was based on a machine Jazz had shown me some photos of and I really liked the compact aspect of it and the moveable bed design.

So I guess its a case of watch this space over the next month and hopefully I will be back up and running with a shopping list a workable design to go with it. Thanks to everyone so far for their inputs and guiding me in the right direction.

fvfdrums
03-10-2013, 01:16 PM
Quick question that I was trying to get answered earlier in the year but never got a definative so I thought I would get "paint" involved.

I was wondering if the BK12 bearing units have a rubber seal in them before the 2 bearings in the houseing and if so does the machined end of the ballscrew stop at this seal or the black part at the back of the unit or doe it fit right up to the bearings inside the unit. Picture attached is it A or B or even C and I am way off!

On a separate note I am awaiting the arrival of some profile rail and bearing carraiges, managed to find a good deal in the end and they are now in the country according to Royal Mail and out for delivery so there is a chance they may turn up today which would be great.

Clive S
03-10-2013, 01:43 PM
If I am not mistaken it is more like B but there is a little spacer at each end of the bearing so that the ball screw does not squash the rubber seals. Be in mind that you will have a bit of free movement at the BF end as the bearing can float in it, say about 3mm. ..Clive

Jonathan
03-10-2013, 01:53 PM
If I am not mistaken

You're not mistaken :)

fvfdrums
03-10-2013, 03:17 PM
Thanks for the replies, I also had one from Chai and confirmed the same thing I am actually planning on using the bk12 on both ends so wanted to make sure where the ball screw ended in relation to the placement of the bearing blocks.

fvfdrums
03-10-2013, 03:21 PM
Whilst i am here, this machine will have an adjustable bed, I was wondering what peoples opinons are on a sensible distance between adjustment holes? 50mm 100mm? That is how far the bed moves up and down between one set of holes and the next

Jonathan
03-10-2013, 06:15 PM
Thanks for the replies, I also had one from Chai and confirmed the same thing I am actually planning on using the bk12 on both ends so wanted to make sure where the ball screw ended in relation to the placement of the bearing blocks.

There's two reason to use angular contact bearings (bk12) on both ends of the screw. One reason is it increases the axial stiffness of the screw, since you have twice the number of bearings supporting it. The other reason is it raises the critical speed of the screw, so you can spin it faster without it whipping. For the vast majority of DIY builds, the stiffness of the screw is at least an order of magnitude greater than other parts in the axis, so you're unlikely to see a tangible gain from doing so. The critical speed however is important, but for the 1610 screw you've chosen you'll be able to get good feedrates so long as the screw is no longer than 1500mm. According to an earlier post ('1200x900 footprint area with approx 1000 x 800 cutting area'), your machine is well below this length so using two BK supports on each screw will only increase cost with no useful gain.

(Search on google for 'Ballscrew stiffness calculation' and 'ballscrew critical speed calculator' if you want a reference for the above.)


Whilst i am here, this machine will have an adjustable bed, I was wondering what peoples opinions are on a sensible distance between adjustment holes? 50mm 100mm? That is how far the bed moves up and down between one set of holes and the next

It depends on your Z-axis travel. Also no need to have them evenly spaced, why not have more holes nearer the place you expect to be using the bed most often and less at the limits? In the past I've gone for 60mm spaced an 50mm spaced, simply because that what the size of the box section I used. You'll probably only move the bed about once a year anyway! I'm not sure I've even moved mine that often, and the latest machine is so much stronger that it doesn't matter where you put the bed.

MikeyC38
03-10-2013, 08:42 PM
Hi

Thanks for the replies, I also had one from Chai and confirmed the same thing I am actually planning on using the bk12 on both ends so wanted to make sure where the ball screw ended in relation to the placement of the bearing blocks.

Glad to hear that you have restarted your project. So have I and I've just ordered my aluminium plate for it. I noticed that you are going to use BK12/BF12 bearings - I have 2 pairs surplus to my build as I am using FK12 and FF12 instead on the Y and X axis. If you are interested, pm me andwe can come to some arrangement.

I will be officially opening my build log soon!

Regards
Mike Campbell

fvfdrums
07-10-2013, 05:06 PM
Ok, so today started with me making a 5 mile trek with these linear bearings on my shoulders all the way across nottingham becuase the other half has the car and is away for a week and there was no one around to grab a lift from (I know I could have got a taxi but that would have been some of the cnc fund ;) ) Anyway I would not recommend it.

Having said all that when I finally got back home and inspected the package it was extremely well packaged and I would not hesitate from ordering from FA Systems from ebay again or recommending them. They were extremely easy to deal with even had a bit of negotitations with them for a better deal on price and postage and they arrived in 5 days from Korea. I got stung for a little Import duty but overall it was a great deal.

The bearings themselves hardly look used, they are well greased and run smoothly up and down the rails which also are mark free so all in all very happy indeed.

@ Mike - Thanks for the offer but I have just placed an order with Chai so I already have these parts on the way otherwise I would have been in touch. I look forward to seeing your build come together.

So due to the dimensions of the rails it has meant we have a slightly different sized machine now, its 1130 x 1060 with a cutting area of 940 x 940. The redesign of the machine is going well and even though I would have rather had the original files to work from its bee refreshing to tackle the design from the ground up and incorporate some of the great ideas people have come up with over the last year since I put the original together.

fvfdrums
17-10-2013, 07:13 PM
More ordering done from overseas!!

We got a great deal on the motors and drivers so now we have 1 x nema 34 and 2 x nema 23 plus 3 of the 7.8amp drivers coming in the next 5 days or so.

Also the order from Chai has been processed now and is also enroute so once everything is here and checks out I think its time to get on to Aluminium warehouse and start the gantry build!

btw: Chai was extremely patient and helpful even pointing some things out I missed and I did not feel the language was a barrier at all. Hopefully what arrives is as good as the service

JAZZCNC
17-10-2013, 07:34 PM
btw: Chai was extremely patient and helpful even pointing some things out I missed and I did not feel the language was a barrier at all. Hopefully what arrives is as good as the service

Chai is a top bloke and he's saved my bacon a few times when ordering stuff because I've forgot to add BK/BF bearings and he's sent them anyway. Suppose that's because he knows I always buy them together but still good to know he's got my back.!!

fvfdrums
18-10-2013, 10:40 AM
Chai is a top bloke and he's saved my bacon a few times when ordering stuff because I've forgot to add BK/BF bearings and he's sent them anyway. Suppose that's because he knows I always buy them together but still good to know he's got my back.!!

Ha ha! exactly the same things with me, so concerend with getting the sizes right of the ballscrews that I didnt even put the BK on the order low and behold the quote came back with the relevant number of bearing housings on the list! The guys great

fvfdrums
18-10-2013, 12:04 PM
Another question?

In peoples experience what is the best size bolts for joining 20mm 6082 plate together in this case for the gantry of the machine? I am thinking of fitting dowel pins in place once the whole assembly is together to aid with reassembly should it need taking apart in the future?

Jonathan
18-10-2013, 12:10 PM
Not much point using bigger than M8, so most people use that.

To aid alignment when assembling you could machine reference edges on the relevant plates, if you've got a milling machine?

fvfdrums
18-10-2013, 12:26 PM
I have got a mill but its not big enough for the cross pieces at 1100mm long to do that. I could maybe do reference edges on the side plates.

Thanks for the info on M8 :)

JAZZCNC
18-10-2013, 04:46 PM
I use M8 for bolting together the Gantry your copying. M5 for fastening profiled Linear rails.
In general you'll need an assortment of M5,M6, M8.

Depending on how your fastening Steppers then you may want M4 But I tend to use M5 and tap the stepper. If your bolting thru stepper then some times depending on stepper frame M5 socket head will touch motor side, not always but does happen. I just whiz head against bench grinder rather than use M4. I try to keep different bolt sizes to minimum, fewer tools needed and less variety of bolts required.
If tapping the stepper you can use M6 without any problems but M6 is no good for bolting thru stepper has head is much too large.

fvfdrums
18-10-2013, 05:06 PM
Thanks JAZZ that's all really useful to know.

The nema 23 inside the gantry is bolted face on to a plate that uses a screw to adjust the tension and another to lock it off so I would imagine bolting straight through with m6 tapped frame in the motor will work well there.

As for the z that will probably be the m5 (with head modified if needs) as the design calls for it to be bolted to the mount rather than the other way round.

Hopefully I can get the gantry built over November if work allows and then have December to get the frame cut and welded up for the base.

I have not put any feet on the frame design and was thinking about sitting it on a concrete pad in the garage that I will run some levelling screws over. Does this sound like an ok base for a machine like this? I will be bolted down ideally which is why I'd rather it was as level as poss to avoid distortion to the frame

Or should I bolt it down as I weld it up?

JAZZCNC
18-10-2013, 08:29 PM
I have not put any feet on the frame design and was thinking about sitting it on a concrete pad in the garage that I will run some levelling screws over. Does this sound like an ok base for a machine like this? I will be bolted down ideally which is why I'd rather it was as level as poss to avoid distortion to the frame

Or should I bolt it down as I weld it up?

Best if bolted down but it will be heavy anyway so won't exactly float away. Thing you need to avoid is not putting machine in twist.
Don't know how you plan to get X axis rails on same plane but which ever way then do it after the machine has been situated where it's going to live and fastened down.

Don't bolt it down has your building it. When building try to find level and flat surface that is not in twist to work from, don't just work from floor unless you absolutely know it's perfectly flat and not in twist. If you don't have decent surface then It's worth taking the time to build one. If the work surface is in twist then the frame will be in twist when welded up.

fvfdrums
18-10-2013, 10:12 PM
My original idea was to pour a temporary surface to do all the welding on and then remove this once done.

Alternatively I suppose I could make a torsion box to assemble from.

fvfdrums
21-10-2013, 01:06 PM
Got a text at 7am this morning to say the Motors and drivers should be here today, thats crazy they were collected in HK at 10pm on friday night and are here this morning now thats service!!

So hopefully I should be able to add a few more pics to the component pile.

I had "yet" another question, whats the smallest or should I say recommended diameter for a 5mm pitch HTD timing belt pulley running 1:1 - is there a minimum number of teeth people would recommend (other than as many as possible) being in contact with the pulley at any one time?

The reason I ask is not for the z or the y as they are simple straight connections with the pulleys in front of each other.

Its the X where I am driving the two screws with the single belt, I can get half the way round the pulley on the left hand side however on the side with the motor I am going to have to put in some idlers to make the belt contact more with the pulley so I can nearly get about 120-130 degrees around one side of the pulley would this be enough?

I thought about doing one belt connecting the two axis and then stacking another pulley on top of the right one and driving this but my concern was "if" the belt were to snap (the long one between two axis) then one side would still be driven by the drive pulley and could cause some bending if it carried on and the other stayed still. Where as if the one belt were to go they would both stop.

Suggestions?

JAZZCNC
21-10-2013, 03:35 PM
Wouldn't go lower than 20T.

Regards the one belt connecting 2 screws then that's how my machine runs and I've not snapped a belt in 6 years use so wouldn't worry about it.!
If you want to be extra careful then use spring loaded NO limit switch with bearing on end tensioned against the belt and wire in series with E-stop so if belt breaks tension releases and causes an E-stop.

fvfdrums
21-10-2013, 03:49 PM
I think I have them as 24 teeth at the moment so i guess that should work.

Motors and Drivers have just arrived. Well packaged and look good so one more package to come from Chai and I can start on the Gantry. I would just rather have the parts with me to measure from before I start drilling and cutting.

How long does Chai generally take to get things machined etc once the order has been placed? I know it takes 1-2 weeks to ship.

1047710478104791048010481

JAZZCNC
21-10-2013, 06:58 PM
How long does Chai generally take to get things machined etc once the order has been placed? I know it takes 1-2 weeks to ship.

Can't tell you that but Usually arrive between 9-12 days from placing order. Often any delays comes from UK end.!!

24T will work fine.

fvfdrums
22-10-2013, 05:32 PM
Had a reply from Chai, says it should be 9-10 days from now as something to do with fed ex and HK I did not quite understand but nice to know they are on their way.

So I have been thinking about siting this machine on a concrete slab poured on top of my garage floor which currently is not particularly level. Has anyone done this before? if so what sort of thickness do you think I would need? I was thinking I could lay down about 1" and then screed the top with a self level compound?

Then once I have built the frame bolt that down to the pad (hopefully eliminating too much twist) and then do some of this wizardry with self leveling epoxy?

Does this sound overkill or feasible? I am going to this much effort on the machine I would hate for a wonky floor to put pay to the accuracy.

JAZZCNC
22-10-2013, 06:17 PM
If your planning to leave in same place all time then I'd just bolt it down something like level then epoxy level.

If your planning to build off the pad then yes it's worth taking time to get flat and level. THE most important bit is building off a flat surface that's not in twist.

Have thought about epoxy levelling the floor.? When I worked for Honda we had epoxy levelled pads for accurately setting Suspension.

fvfdrums
22-10-2013, 06:32 PM
Its going to be in the same place for the foreseeable - (until the other half decides she wants half the garage for something)

I was thinking of using the pad to build the frame sections on to make sure they were flat and true (more so than garage floor!)

Then assemble to whole thing on the pad and bolt it down.

How thick would the epoxy need to be? I am just reverting to cost here probably be able to deal with a slab as I can get all that on trade no sure I can the epoxy! heres hoping though :)

fvfdrums
22-10-2013, 06:43 PM
Whilst i am here....

.... I have been thinking about how to tackle the bed design. Initially it was going to be steel frame with an ally plate then strips to make up t slots however I am now thinking why not use the steel frame (60mm depth from the box section) as th catch tank for the coolant?

So box section steel frame which is the moveable bed. 20mm thick aluminium strips running 90 degrees to the box section cross members. either an aluminium angle edge maybe something like 4"x1" to prevent some of the splash getting everywhere or just some 3mm steel flat bar on its side welded round the edge. Then on the bottom of the steel box section a sheet of something like acrylic or polycarbonate which is sealed against the bottom of the frame (rubber gasket and a silly amount of bolts) obviously I would need to create some sort of fall so the coolant went back down towards a collection spout.

Would this work? or is there a better way of doing it? Apologies for all the questions today had a boring job to do which required very little brain power!

JAZZCNC
22-10-2013, 08:31 PM
Would this work? or is there a better way of doing it? Apologies for all the questions today had a boring job to do which required very little brain power!

My bed is done this way and yes it works fine. I looked at many choices before going this route but all other options where far more expensive.
One large piece of plate with a matrix of holes was the preferred choice but far to expensive and also came with little scope for cock-up's. With the strip system then I can just replace any strips that get damaged.

Many ways and lots are equal or better but IME any that are better will be quite a bit more expensive.

fvfdrums
02-11-2013, 01:23 PM
Still no sign of the ballscrews, been tracking the fedex shipment but Chai says fedex had a warehouse explosion or something and now everything has had to be reordered in terms of when its shipped so I guess I am in the hands of the Logistical Gods!

JAZZCNC
02-11-2013, 03:55 PM
Still no sign of the ballscrews, been tracking the fedex shipment but Chai says fedex had a warehouse explosion or something and now everything has had to be reordered in terms of when its shipped so I guess I am in the hands of the Logistical Gods!


Yes I'm waiting for stuff has well and it's been stuck in Hong kong for 11 days and just checked it's now in France so hopefully may see it UK next week if the Frogs aren't on strike again, then well hopefully see it in months time after the Lazy arse UK customs decide to process it.!!

fvfdrums
02-11-2013, 06:29 PM
Yeah mines just made it to Stanstead, it spent all yesterday in France so looks like things are moving a bit.

fvfdrums
04-11-2013, 01:31 PM
So fedex finally arrived this morning with a parcel from Chai,

Packaging was a bit limited compared with the other parts I have recieved from China. Upon inspection it looks like at least two of the longer ballscrews have quite a bit of a bend to them. I dont have a dti to hand but turning them I can see it by eye.

Is this a common thing? and how does one go about straightening them ?

I knew it was all going too well :)

Jonathan
04-11-2013, 01:35 PM
Is this a common thing? and how does one go about straightening them ?

I've got round it in the past by ordering ballscrews and rails at the same time, since the rails add sufficient strength to the package, but if you're getting the rails elsewhere that's not much use.

How long are the bent ballscrews? You can try clamping it between V-blocks, and pushing down in the middle to bend it back... but it's not going to be easy.

fvfdrums
04-11-2013, 04:30 PM
I've got round it in the past by ordering ballscrews and rails at the same time, since the rails add sufficient strength to the package, but if you're getting the rails elsewhere that's not much use.

How long are the bent ballscrews? You can try clamping it between V-blocks, and pushing down in the middle to bend it back... but it's not going to be easy.

Rails already in my possession but ill keep that in mind for the future!

I am going to put it in my lathe later and try and measure how far out it is. But any ideas greatly appreciated

JAZZCNC
04-11-2013, 07:10 PM
My stuff arrived today has well, wonder if they came on same shipment.? Don't know if dare say this but my stuff is ok but I did have other stuff which supported the screws plus they where only 1300mm long.

Depending how bent then like Jon says V bollock and plenty of force, I've straightened screws before but it's slow process and easy to over do and bend more.
If not too bad then I'd fit on machine and see how they perform, sometimes they can be ok when running and not affect machine too much.?? . . .they can also shake the bastard to bits but worth a try.!!

fvfdrums
04-11-2013, 07:51 PM
My stuff arrived today has well, wonder if they came on same shipment.? Don't know if dare say this but my stuff is ok but I did have other stuff which supported the screws plus they where only 1300mm long.

Depending how bent then like Jon says V bollock and plenty of force, I've straightened screws before but it's slow process and easy to over do and bend more.
If not too bad then I'd fit on machine and see how they perform, sometimes they can be ok when running and not affect machine too much.?? . . .they can also shake the bastard to bits but worth a try.!!

Mine are only 1050mm long but it was just the 4 ball screws bk12 holders and the ball screw holders in the one package covered in yellow tape and a sprinkling of bubblewrap. Oh well hopefully they are not as bad as they feel but I have a horrible feeling :|

njhussey
05-11-2013, 02:49 PM
My ball screws from Chai were wrapped in plastic, encased in foam and wrapped in a cardboard square tube/box which was liberally wrapped in yellow tape. Not checked mine yet to see if they're straight....might be doing that sooner rather than later now!!

fvfdrums
16-02-2014, 10:54 PM
So......

A fair bit of work this weekend and the basic frame of the gantry is done. Lots of measuring 4 times and drilling once but its all worked out really well everything is nice and square and meets up well could not be more pleased.

I have to say a big thank you to Jonathan for organising for the gantry sides to be cut so quickly, collected this morning and on the gantry by this eve.

Now its started I dont think I will be out of the workshop for a while, good job the missus has gone to South Africa for two weeks!

:)

fvfdrums
23-02-2014, 05:36 PM
Another weekend of work and the gantry is really coming together now.

Got the y axis ball screw fitted, motor mount machined and fitted inside the gantry, x axis bearing plates milled and drilled and test fit on the rails on some trestles.

Looks like I need to get some more material together for the z axis!

btw, the x rails are screwed onto the trestles I was a bit concerned one side might just fall off!

JAZZCNC
23-02-2014, 06:35 PM
Did you really need to over build the base frame that much and how do you plan to attach the ballscrews and motors to the trestles.?. . . . Lol

Looking Good Francis sorry I was too busy to help with machining but looks like it's coming along nicely, keep up the good work. .:encouragement:

fvfdrums
23-02-2014, 07:27 PM
probably not but I can always have the parts out and pocket sections of the parts which dont need quite as much strength in the future.

Thanks for all the init and I know your busy so its not a problem :) hopefully it keeps going as smoothly.

EddyCurrent
23-02-2014, 08:27 PM
That is one meaty and sturdy gantry and quite a good design.

fvfdrums
23-02-2014, 08:29 PM
i cannot take credit for the design - well other than my version of...... it was a design jazz put up ages ago that I took the cues from

JAZZCNC
24-02-2014, 02:56 AM
probably not but I can always have the parts out and pocket sections of the parts which dont need quite as much strength in the future.

Thanks for all the init and I know your busy so its not a problem :) hopefully it keeps going as smoothly.

!!!!. . .You did realise I was taking the Piss with the comment about over building the Base Frame(trestles). . . !!!!

Don't be surprised if the build and progress slows down they always do at some point and the things seem to fly along then just crawl for no apparent reason.? . . . .Just keep pluging away and it will happen.

fvfdrums
24-02-2014, 01:36 PM
Sorry! read it wrong thought you meant the base of the gantry!!!

Yeah the trestles are the way forward in cmc frame work torsionally perfectly no movement and you can fold it away after use :)

Well just ordered the materials for the z axis so thats next, i think there will be a lull before we get the steel framework done and then it will be all the fiddly bits that take the time!

fvfdrums
28-02-2014, 09:34 PM
More materials arrived so looks like it won't be too long until the y and z are done!

Plus turned up a few stainless parts for various bits around the machine :)

EddyCurrent
28-02-2014, 10:11 PM
Are you still going to mount the Z axis motor on 4 posts like in an earlier drawing ? I think it's a better idea to mount it on a piece of box section so that the pulley and belt are inside the box, motor mounted on top.

fvfdrums
28-02-2014, 10:14 PM
Eddy,

Yes its still going to be mounted on the 4 posts, the tensioning system is not pictured in the original drawing but is part of the posts. Once the machine is fully constructed I will be buiding some thin sheet covers for all exposed areas and have won some good machine bellows for the linear rails.

fvfdrums
02-03-2014, 09:12 PM
Long day in the shop today, but very successful thankfully.

Started out making up a block to machine the front plates on, my combination mill and lathe has one real flaw and that is the spindle working ant any major extension and it becomes very inaccurate so I needed to find a way of building the bed up. So I bolted together a bunch of 20mm aluminium plates and surfaced the whole thing and it worked perfectly, somewhere I could clamp the pieces down safely and solid in order to machine the surfaces near the top of the mill.

I machined up the top and bottom bearing plates first and faced the edge that was going to meet the y axis front plate (as the standard plate saw sits from the supplier seem to have a draft angle of about 1 degree) and then it was onto the main plate which I stepped to fit the top and bottom plate by 5mm.

A few holes and it was all together very nicely, its quite nice making the plates to "fit" the machine thats in front of you rather than having it all made up in kit form I can now see the benefits.

So all in all a very successful day, y axis slides left to right very smoothly with no tight spots whatsoever all dialled in with a DTI.

I have mocked up the z axis so still need to do some machining on the front plate of the Y for the ballscrew and surfacing for the bearings but with this new mill setup this should be a breeze! (won't speak too soon)

EddyCurrent
02-03-2014, 09:27 PM
It makes a nice job when you have a proper milling machine. I like how you stepped the main plate, it makes a good solid joint, the whole thing looks great.

fvfdrums
02-03-2014, 09:53 PM
Originally I was going to have a load of parts cut for me but I as I was not sure my Mill was up to the job, or the long runs needed 400mm plus in some cases however I sort of took the bull by the horns in the end when i couldn't get them all done and bought some good measuring devices which makes all the difference.

Also spending time to get the correct cutters, feed speeds, and DOC are important. Luckily I used to run a large CNC lathe and had a load of high quality end mills left from this which just turn aluminium into lovely little chips so its not so much a problem but like I said the play in the spindle when extended on the mill is not good so trying to get the workpiece as close to the start point of the mill was important. After that is was surprisingly satisfying :)

GEOFFREY
02-03-2014, 11:30 PM
Looking good, well done. G.

njhussey
03-03-2014, 09:43 AM
Looking good :thumsup:, getting jealous of everyone's build...especially as you all seem to have lots of nice tools to make it with. (Note to self...must get my DIY spindle mounted in something so I can cut my Ali plate and start making my bits...)

EddyCurrent
03-03-2014, 10:18 AM
(Note to self...must get my DIY spindle mounted in something so I can cut my Ali plate and start making my bits...)

That's a great idea that never crossed my mind, maybe use an cross vice underneath it ?

njhussey
03-03-2014, 10:52 AM
I was thinking of making a dolly for it out of MDF and using it as a hand router but with lower speed/more torque as got a 104A 24V PSU (2 server PSU's in series) I'm going to use with my 100A ESC and servo tester, for speed control.

11742

Jonathan
03-03-2014, 11:17 AM
but like I said the play in the spindle when extended on the mill is not good so trying to get the workpiece as close to the start point of the mill was important. After that is was surprisingly satisfying :)

Part of your problem with rigidity on the mill will be due to using a drill chuck for milling. Drill chucks are not designed for radial forces, since drills apply a largely axial force. For that reason you shouldn't use a drill chuck for milling as they don't grip very well, in addition to being prone to have higher runout. Get an ER collet chuck and set of collets off eBay and I'm pretty confident you'll see the difference. Just get a suitable size one with the right taper etc...

Lee Roberts
03-03-2014, 09:19 PM
To add to JB's comments, tapered drill chucks like to come lose and drop out when applying a side cutting force - using something like an end mill in a drill press. So can be dangerous both to you and the part, be safe guys....

.Me

Jonathan
03-03-2014, 11:16 PM
To add to JB's comments, tapered drill chucks like to come lose and drop out when applying a side cutting force - using something like an end mill in a drill press. So can be dangerous both to you and the part, be safe guys....

On a milling machine the drill chuck is generally held in with a drawbar, so it shouldn't drop out. However, the drill chuck's poor ability to support the cutter radially would make the cutter prone to dropping...

fvfdrums
05-03-2014, 10:07 PM
Jonathan, Thanks for that I will do that and see what its like :) I do always use a drawbar with my mill head as the last thing I want is the chuck dropping out and hitting me let alone the piece of metal I have been working on for hours!

I got on to machining the front side of the y axis plate and it again went very well, managed to get the surface nice and level even though it had to be done in two sections as my mill table is not long enough for one pass.

I then milled the base of the bk mounts and the ball screw holder to get the whole thing to close up a bit more without hogging out more of the aluminium plate than I needed to. I only took a couple of MM off the feet of the bearing mounts but it meant I did not need to cut into the face plate at all.

Ignore the lack of bolts I am waiting on a "top up"

Neale
05-03-2014, 11:00 PM
Looking at your picture, you have the Z ballscrews bearings bolted to the fixed Z plate, and it looks as if the ballscrew nut will bolt to the moving Z plate. How are you going to adjust the nut or bearing position, or the guide rails, so that everything is nicely aligned? I've been looking at these details on my own design for a while and am looking for inspiration! I have some ideas, but always keen to re-use other people's work...

Skysurfer
06-03-2014, 10:16 AM
Sounds a bit similar to the machine I could do with building...I'll be keeping an eye on your build.
If you're buying on fleabay, just a tip... Don't buy anything online after a visit to the "Trip" (To Jerusalem) :cupcake:
Good luck.

fvfdrums
06-03-2014, 10:47 AM
Done plenty of buying after going to the Trip! But no CNC parts mind :)

EddyCurrent
06-03-2014, 05:26 PM
Looks like the build is moving at a pace now, Z axis looking good.

fvfdrums
06-03-2014, 06:05 PM
Z axis front plate on the mill as we speak just in for a nessecary cup of tea!

fvfdrums
16-03-2014, 03:30 PM
Been busy for a week or so but have managed to get some stuff done. The z axis is now done and on the gantry which is great, all moves up and down nicely I am leaving fine tuning until its all sat on the frame.

Speaking of the frame I should be expecting the steel delivery next week for the main framework and the weekend after will be a 3 day weekend of getting the frame sorted and the gantry sitting on it hopefully.

In the mean time I have been levelling out a pad in the workshop for it to sit on as I realised after closer inspection that the floor did fall away in the corner where the machine is meant to be going so I thought I would level a specific area for it to sit on which once dried out will hopefully double as a nice flat plate to set the frame up for welding on as well. I have left adequate room around the machine for maintenance once all bolted down.

Few tedious pics of the pad going down

fvfdrums
31-03-2014, 09:59 AM
A decent amount of progress made on the frame this weekend, inspired by the build Jonathan did recently we decided to go down the route of a similar frame but at worktop height so working height of the bed is around 850mm at max settings. All made from 60x60x5mm, took plenty of time to weld up moving around the frame tacking then putting down some good welds so as not to distort.

End result is an extremely level frame in all directions (still will be doing resin but more to level out the bow in the cross section of the steel box section which is very noticeable along its length)

Still need to finish fully welding the frame as the bed is still only tacked but then X axis drive components next!

Skysurfer
31-03-2014, 10:17 AM
I'm a Boilermaker, and run into this all the time. The bow is caused by the shrinkage of the steel after it's cooled from the cherry red of the weld. If it's easier for you, if you heat the opposite side to the weld by roughly the same amount of heat that's gone into the weld (you could weld opposite, then grind flush when finished), it will shrink by the same amount (i.e. straighten). I normally put a torch to the opposite side, and eyeball down it's length until it's bob on.
Always weld opposite the last weld to keep distortion to minimum, but it'll always creep in...
You should put a couple of decent tacks on one seam, then weld the opposite. Then go back & weld over the tacks.
Might save you effort and/or time...Certainly save epoxy...
Really love that gantry, presumably ally? Would love some more details on it. Which supplier did you go to for your rails?
Looking good...

fvfdrums
31-03-2014, 10:34 AM
The bow in this case is consistent along the entire 7.6metre lengths of the steel when they arrived (more of a sag left to right if that makes sense, very subtle but needs to be levelled. The welding process has not accentuated this at all its not in twist intact its very straight as every joint and opposite joint was well held anddidnt really move much after welding due to the short periods of welding

The tacks then weld opposite is pretty much what I did but I did about a 30mm weld on one side then went back to the other then moved to the diagonal opposite part of the frame always checking then diagonals etc and angles for squareness so end result I am extremely happy!

Thanks for the comments :)

EddyCurrent
31-03-2014, 11:40 PM
looking very nice, you won't break your back leaning into it at that height.

fvfdrums
26-01-2015, 12:21 PM
So its been a bit of a while since the last post ..........

...... Anyway things have moved on a little bit and this coming weekend I am about to lay down the x rails for the final time on a bed of epoxy, weather is not treating me to nice temperatures but have a nice set up in the garage now to maintain a good heat source for a couple of days to aid with the curing.

In the mean time I have a question I am about to order the spindle for the machine, originally I was going to go with the 2.2kw WC chinese style spindle however I was wondering if there would be any benefit in going for the 3kw version? I am looking at mainly machining aluminium on this machine and wondered if the large powered unit would be any better? Is it worth the extra?

I shall be putting up some more pictures etc once I have the rails and everything on the machine after next weekend and then probably posting every 5 min asking about wiring the damn thing!

Jonathan
26-01-2015, 12:23 PM
In the mean time I have a question I am about to order the spindle for the machine, originally I was going to go with the 2.2kw WC chinese style spindle however I was wondering if there would be any benefit in going for the 3kw version? I am looking at mainly machining aluminium on this machine and wondered if the large powered unit would be any better? Is it worth the extra?

In short.. yes as the extra torque helps when operating in the lower speed range.

fvfdrums
26-01-2015, 12:27 PM
Thanks Jonathan, I thought that might be the case I was not sure how much difference it would make but really the cost at this stages makes no real difference so I think I will go down that route many thanks.

routercnc
26-01-2015, 01:30 PM
In case you weren't aware the 3kW spindles are usually 100mm diameter, rather than the more familiar 80mm diameter of the 1.5 and 2.2kW units.

fvfdrums
26-01-2015, 01:32 PM
yeah thanks for the heads up I had taken that into account with the mounts one of the other reasons for making the descision so I could finalise those.

3KW version now ordered so getting on boring out the mounts!

fvfdrums
29-01-2015, 07:41 PM
Managed to get a bunch done today which was great!

Earlier this week I had some deliveries in the form of a 3kw spindle and inverter, some west system epoxy and extra slow hardener, some more aluminium plate and a few more essentials to move this project along a bit more.

I started out today machining up a mount for the x axis drive motor which is going to be driving 2 screws with one motor so needed a good mount and also space for a good tensioning system. The parts for the tensioners only arrived this afternoon so I have not had a chance to add those yet but they will be going on the taller part of the mount that the nema 34 motor is attached to.

I have managed to get some heat into the workshop so on sunday I am going to get the epoxy resin poured. Any tips? I have read most of the builds using this and I am sure if I follow those steps everything will work out fine! (heres hoping)

Finally I did not order enough aluminium for the spindle mount so mocked 2 plates up out of polycarbonate I had lying around and fitted that on to make sure I could get at everything for adjusting etc. So far so good all looking great, just need to spend saturday on the X axis mounting blocks and the timing pulleys and should be about there ready to pour the epoxy.

One last thing do people recommend drilling the x axis rail mounting holes before or after pouring the epoxy?

JAZZCNC
29-01-2015, 08:22 PM
One last thing do people recommend drilling the x axis rail mounting holes before or after pouring the epoxy?

Do it after the pour it drills easy and doesn't cause any problems.

One word of warning with the epoxy and this cold weather.? I've just done a pour using 206 hardener which is faster curing and in a thermasticly heated workshop and after being left 5 days I still got a little sinkage after fastening rails. Nothing major but still enough to need a slight shim to avoid putting bind on the bearings.
Using the 209 I wouldn't touch yours for at least 10days. If you have any spare epoxy pour a little into something to simulate the width and depth your doing and then wait until it's gone hard so snaps when trying to bend. If it bends and doesn't break it's not ready. The surface will feel hard to touch but it won't be cured all way thru.

fvfdrums
30-01-2015, 03:04 PM
Cheers Dean! very helpful as ever :)

The plan is to pour it on sunday and then leave it for probably near on 3 weeks as I will be away with work so cannot do anything on it anyway so figured this would be the best option. I am planning on making a sort of tent around the machine and using a 3kw oil radiator style heater on a thermostat to try and keep the temp up. I prefer these to the fan type as at least they are sealed and there is no exposed heating element. This way i am happy to leave it on for extended periods and not worry too much.

I will pour a couple of samples of any remaining material as tests as well so thanks for that. I will look out for the "Snap" test once I am back.

Any suggestions on where is a good place to have a made to order length timing belt? I have yet to find one

njhussey
30-01-2015, 04:27 PM
Do it after the pour it drills easy and doesn't cause any problems.

One word of warning with the epoxy and this cold weather.? I've just done a pour using 206 hardener which is faster curing and in a thermasticly heated workshop and after being left 5 days I still got a little sinkage after fastening rails. Nothing major but still enough to need a slight shim to avoid putting bind on the bearings.
Using the 209 I wouldn't touch yours for at least 10days. If you have any spare epoxy pour a little into something to simulate the width and depth your doing and then wait until it's gone hard so snaps when trying to bend. If it bends and doesn't break it's not ready. The surface will feel hard to touch but it won't be cured all way thru.

I cut my bridge off when the epoxy had been on for 10 days and used that (it was on parcel tape on the bridge so just slipped off no porblems) to do a snap test...made sure this time as I had proper bendy epoxy last time....

JAZZCNC
30-01-2015, 07:40 PM
Any suggestions on where is a good place to have a made to order length timing belt? I have yet to find one

I get mine from a local supplier to my business in Goole called Yorkshire engineering services give them a ring they will sort you out I'm sure. 01405720085

fvfdrums
03-02-2015, 09:37 AM
Another good weekends work out of the way...

So a slight change of plan, after heeding the warnings of laying out resin in the cold and the temp around here steadily dropping it was decided that we would attempt to see how level we could make the machine using various measuring methods and after an hour or so of painstakingly shimming and adjusting the base the top was where we wanted it to be.

A few cups of tea and staring later the straight edge I ordered arrived and from this we could see using feeler gauges there was a pretty consistent shallow curve from one end of the steel to the other mainly due to the welding around the middle of the machine as this was within 0.05mm at the same point on either side of the machine.

As the difference was not all that large we decided to embark on shims and the possibility of using epoxy putty if needed. All I can say is dont be put off by having to shim rails! Initially I did not even think I would be able to get it near close what we needed however a couple of hours of filing high spots and then measuring using a feeler and inserting the correct piece of shim steel and we had the rails matching the straight edge.

The gantry moves smoothly from one end of the machine to the other no tight spots and I just need to get hold of a DTi in order to do some final checks however all in all I am very happy with the results.

Fitting the x axis screws however was a PITA....

The first one went on fine, no binding alignment was great everything slid in place.

The second one is really bent :( I thought it was a bit bent when it came from Chai - i registered a complaint but heard nothing back after 2 emails. However with one end bolted down and the ball screw holding it steady one rotation of the thread results in the loose bearing mount the other end moving up and down about 2-3mm dependant on what part of the thread you are on.

Does anyone know anywhere I might be able to get this straightened? I have no access to a hydraulic press or anything precision enough to make this good? any suggestions?

This aside its all on and screwed in place and a few turns of ballscrews here and there results in a pleasing movement across the machine. The only other issue is there seems to be a large amount of end float coming from the bk bearings I have either end so I am going to disassemble them and see if they need shimming in the middle!

All in all a successful weekend :)

EddyCurrent
03-02-2015, 10:17 AM
The second one is really bent :( I thought it was a bit bent when it came from Chai - i registered a complaint but heard nothing back after 2 emails. However with one end bolted down and the ball screw holding it steady one rotation of the thread results in the loose bearing mount the other end moving up and down about 2-3mm dependant on what part of the thread you are on.

Does anyone know anywhere I might be able to get this straightened? I have no access to a hydraulic press or anything precision enough to make this good? any suggestions?


This was Chai's response to my bent screw;

Before shipping, we tested the ballscrews VERY SERIOUSLY as the following standard:
The ballscrew assembly (Ballnut and Spindle assembled) Precision rolled, class 7 accuracy; JIS (0.050/300mm) (0.002"/12")
Ballnut: Single ballnut with zero backlash (<0.015mm) (0.0006")
Please refer to the link:
http://www.roton.com/screw_shaft.aspx
YOU can addust it if necessary.


Also here's some info on fixing those bearings; http://www.mycncuk.com/threads/6565-Ready-Steady-Eddy?p=56128#post56128

JAZZCNC
03-02-2015, 03:50 PM
If you identify the bend location you can make a fair job of straightening these screws using a vice and 3 blocks of wood. You'll be surprised how much bend the screws will tolerate before becoming a problem. Obviously any bend will have a little impact on the life of the screw/nut but IME even moderate bends won't affect machine performance to much and last years without any problems. I doubt you'd still have machine before it became a problem and when it does you'll be ready for changes and upgrades.

Regards the BK bearings then check the bearings are not in wrong way around which often happens. I strip every bearing to clean/re-grease then shim and every other one the bearings are in wrong way around.

fvfdrums
06-02-2015, 02:12 PM
I have had a play around with the bearing blocks, all of them had both bearings facing the same way round rather than back to back, also there was a larger amount of slop in at least 4 of them so I have ordered some alternative bearings to replace with as I was getting 0.4mm of end float once everything was tightened up.

So whilst I am waiting for bits to arrive I am trying to source some bits I was wondeing if people could let me know if they have any suggestions for the following?

e Chain? - have found a reasonable supplier on eBay for it so might just go down this route about 10-15 for a metre

Breakout board combination: Can someone tell me if I go down the PMDX or smooth stepper route what I would need. I did not order a BOB when I bought my stepper drivers as I had heard so many people knocking the cheap BOBs. So my question really is which of the two do I go for SS/PMDX and if so what do I need as well as this to connect to mach 3 (I am not talking limit switches etc I just mean between stepper driver and PC)

Finally now I have the rails levelled using shims I have a litre of WS resin and 209 hardener I dont use I would be willing to let go for a good price if people are interested please IM me :)

JAZZCNC
06-02-2015, 03:05 PM
First I'll take the resin if you still got it.!! I'll PM you

routercnc
06-02-2015, 07:52 PM
Looking really good now well done. I wasn't happy with my 2 X-axis ballscrews so sent the worst one away to be straightened using a hydraulic press. My original post is here:
http://www.mycncuk.com/threads/7160-ballscrew-straightening?highlight=bent+ballscrew

Looks like I never followed up this post but it came back really straight and ran sweetly in the bearings.

I decided not to send out the ballscrew which was only slightly bent and fitted it to the machine instead. As Jazz mentioned there were no noticeable problems.

I know your spindle mounts are only temporary perspex parts, but I assume the real parts will be much thicker (my first ones were 20mm aluminium and worked well).

fvfdrums
06-02-2015, 08:44 PM
Thanks it's nice to be finally getting somewhere!

It just so happens I have justified a 12 ton press this week as my van needs all it's bushes replacing and for the cost of the bushes and a press I've saved a heap on garage costs so I may well set up some v blocks and have a go at that.

Running them up and down I have noticed the bent one is considerably more noisy than the straight one

Boyan Silyavski
08-02-2015, 04:57 AM
So you too like Justifying? :hysterical: I have my garage full cause of this...

Dont forget to grease the screw right now. In all tech docs is said the screw should be greased /oiled/ prior to putting to use.

fvfdrums
09-02-2015, 10:41 AM
Thanks Silyavski :) yep justification is key!

Whats the best kind of grease for the screws and bearings?

Boyan Silyavski
09-02-2015, 06:47 PM
Hiwin Lubrication (https://www.google.es/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CDoQFjAB&url=http%3A%2F%2Fwww.intercom.si%2Fweb%2Fdokumenti %2FHIWIN_LI_EN_V1_1.pdf&ei=ye_YVK72IMH0UvLpg5AC&usg=AFQjCNGCSC1dv_K_S5BlFMQ0fYw73_QGtQ&sig2=GUA9KdAMcPnO5ZjeAzhLdQ&bvm=bv.85464276,d.d24) Guide, in short any grease or oil that has no solids like Mo and Graphite. That includes WD40 too. That would be any normal bearing automotive grease which says NLGI2

I used yesterday normal lithium grease that said NLGI2. I thought of making central oil system but at the end decided against it, too much hassle and extra cash to do it properly, when i could simply use the grease gun and forget about it.




Grease lubrication

Grease lubricationFor grease lubrication, we recommend greases in accordance with DIN 51825 of consistency class NLGI 2 as specified by DIN 51818.


For normal loads, standard greases with the designation " K1K are sufficient.


For higher loads (P/C < 15), high-pressure lubricating greases are required: " KP1KThe use of greases of other consistency classes is possible subject to the approval of the lubricant supplier.


NOTE Greases with solid particles such as graphite or MOS2 must not be used.The following information on lubricants serves to provide examples and is only intended as an aid to selection.




Oil lubrication

Lubricating oils offer the advantage of more even distribution and reach the contact surfaces moreeffectively. However, this also means that lubricating oils collect in the lower area of the product asa result of the force of gravity and thus more quickly cause soiling. For this reason, higherquantities of lubricant are required than with grease lubrication.

Oil lubrication is as a rule onlysuitable where a centralized lubrication system is used or for products equipped with a lubricationunit.Observe the lubrication system manufacturer's instructions.The following information on lubricants serves to provide examples and is only intended as an aidto selection. Other lubricants may be used after clarification of the specific application and thecentralized lubrication system used with the lubricant supplier.

Lee Roberts
09-02-2015, 07:47 PM
Whats the best kind of grease for the screws and bearings?

Lithium 2 (grease) is what I always suggest, can get a tube for 3 here, can't remember size but it's on par with a tube of silicon sealant or decorators chalk, so quite large for the amount you'll use.

Oil don't last as long but grease clogs up, take your pic.

.Me

fvfdrums
16-02-2015, 04:16 PM
So it looks like its time for some wiring!

I have spent a vast amount of time reading through the forums and over using the search facility (if there is such a thing).

Anyway I am drawing up a wiring diagram at the moment but there are a couple of things I could do with advise on.

I have decided to go with the CS Labs CSIMO -IPM as it seems to suit the machine perfectly as its running a single belt to drive both x axis screws. This also means I only need run a separate 24v DC supply for powering the unit and also the safety circuit.

So on to the safety Circuit it is....

I am confident I have the bases covered on isolating the mains supply to the drivers on fault or Estop however what is the best way to isolate the spindle? as I have been reading removing power from the inverter is not always a good thing? what are people doing to make the spindle safe in an estop senario? (chinese 3 kw spindle setup)

That then brings me on to drives, when I started the machine (many moons back) the drive and motors were ordered from china I was under the impression we were getting digital drives, having glanced over them at the time I did not really take any notice but it appears we have 3 of the DM860a drivers. Now given that this much effort has been put in I am thinking its worth switching these units out for the AM882 of the EM806 drives? Would this be a good move or a waste of time?

If a good move then I have 3 brand spanking new DM860 drives for sale if anyone is interested please PM me!

Thanks as ever for the on going support from an incredible knowledge base!

Boyan Silyavski
16-02-2015, 07:13 PM
So on to the safety Circuit it is....

I am confident I have the bases covered on isolating the mains supply to the drivers on fault or Estop however what is the best way to isolate the spindle? as I have been reading removing power from the inverter is not always a good thing? what are people doing to make the spindle safe in an estop senario? (chinese 3 kw spindle setup)


When BOB is reset it stops giving On signal to VFD ON input so the VFD stops, hence VFD low voltage On is chained on the Estop line.




That then brings me on to drives, when I started the machine (many moons back) the drive and motors were ordered from china I was under the impression we were getting digital drives, having glanced over them at the time I did not really take any notice but it appears we have 3 of the DM860a drivers. Now given that this much effort has been put in I am thinking its worth switching these units out for the AM882 of the EM806 drives? Would this be a good move or a waste of time?



Waste of time, these are good DSP drives. Almost the same as the AM882.

Boyan Silyavski
16-02-2015, 07:24 PM
However if you have the simplest 3kw inverter like the diagram below, care should be taken what voltage flows there. So if you board is 5v and the inverter is 24v or vice versa. Best would be that you have an Estop button with double switch circuit or you just use an enable output on Mach3 and a relay on your BOB.

http://www.mycncuk.com/attachment.php?attachmentid=14676&stc=1

JAZZCNC
16-02-2015, 10:04 PM
Depends how Anal you want to get.!!! . . . Really with an emergency stop then power should be removed. Just removing the RUN signal isn't compleltely safe.

Killing power to the VFD isn't ideal but in a true emergency then it's what you want to happen. It can be done safely using timer relays to allow time for spindle to shut down safely before power is removed.
Is it really needed.? Well only you can answer this one.! . . . Me i'm happy to isolate the run signal using a relay, Which by the way the IP-M as built into the controller so can connect direct to the VFD.

Drives because you have them I'd stick with and they'll do the job ok but NO they are not good as the AM or EM which are much smoother refined drives. Just because they use a DSP doen't make them the same.!

fvfdrums
16-02-2015, 10:13 PM
So in a nutshell - what benefits am I likely to notice between the DM and the AM/EMs? I know they have the stall detection is that as vital if I am only running one motor for the x axis? or have I missed the point...

I think the run signal works for now. I can see this panel taking as long as the bloody machine at this rate!

fvfdrums
16-02-2015, 11:22 PM
Also,

just reading through the manual for the BoB it suggests if using a large contactor to switch off the power its an idea to have a diode and a noise suppression device? is this to prevent voltage spikes? and how would one go about adding these to the control panel?

JAZZCNC
16-02-2015, 11:34 PM
In a nutshell you'd get smoother movement from the motors, esp at lower speeds. Also less motor heating as they handle current much better and the drives software seems much more refined.
These things I know for sure just from the limited experience of the DM's vs AM/EM which I've loads of experience with.
While I can't answer this 100% because my experience with DM was limited I'd take an educated guess and say you'd get slightly less speed/torque compared to EM as well.
This said I still wouldn't sell the DM if you have them as the difference in use will be minor but there is a difference. The stall detect isn't an issue at all for you so don't fret about this and you haven't missed any point.

fvfdrums
17-02-2015, 07:38 PM
ok so assuming that I use these DM860 drives. What do I do with the enable signal? It says in the manual normally left unconnected (enabled) if i were to use it what would I be connecting it to? Sorry a little confused on that one

IanS1
17-02-2015, 08:03 PM
ok so assuming that I use these DM860 drives. What do I do with the enable signal? It says in the manual normally left unconnected (enabled) if i were to use it what would I be connecting it to? Sorry a little confused on that one

Whichever controller board you decide on, it should have a connection for the enable/disable.

fvfdrums
17-02-2015, 08:14 PM
thanks for the reply, I know they have to be connected to the controller and I am settled on the CS labs CSMIO IPM board which I am sure has a facility for connection of these I am just not sure where they are meant to be connected to on this. Is it a digital in or out? .......

Give me a welder over a soldering iron any day!

fvfdrums
18-02-2015, 08:35 PM
Does anyone happen to know the dimensions of the CSMIO IPM board roughly? trying to source a control cabinet and know everything else size wise apart from this, it does not appear to be in the manual or on the site as far as I can see.

njhussey
18-02-2015, 09:04 PM
http://www.cs-lab.eu/en/produkt-18,2-CSMIOIPM_4axis_Ethernet_Motion_Controller_stepdir_ with_connectors.html

It's on the page :wink:

fvfdrums
18-02-2015, 09:12 PM
some times you cant see the wood for the trees - or in this case I have looked at that page so many times I just plain did not see it, now I have looked I have no idea how I missed that.

Cheers for that!

njhussey
18-02-2015, 09:26 PM
You and me both, I thought it was in the manual till I saw it there....

JAZZCNC
19-02-2015, 04:38 PM
thanks for the reply, I know they have to be connected to the controller and I am settled on the CS labs CSMIO IPM board which I am sure has a facility for connection of these I am just not sure where they are meant to be connected to on this. Is it a digital in or out? .......

Which motion controller you use doesn't matter. All you are doing is using a Output to turn the drive Enable signal on or off.
What matters is the Software Mach in this case has an enable output option for each axis which turns on or off when software is reset or E-stopped. You Assign this enable option to any output pin or pins you choose.
Often you'll just use 1 output and use this to trun a relay on or off which in turn sets all the enables on each drive.

fvfdrums
19-02-2015, 06:22 PM
Thanks Dean

So am I right in thinking that the default on these drives is enabled? unless instructed otherwise as in the manual for the DM it says these are not usually connected, I have seen many wiring diagrams now where they are and I fully intend to just a little confused as to why they would say not normally connected

basically will the drive still work if these are not connected I think is a simpler way of putting this!

JAZZCNC
19-02-2015, 07:17 PM
basically will the drive still work if these are not connected I think is a simpler way of putting this!

Yes they will work fine if not connected. Yes and No to default being Enabled. To understand better how the Enable feature works some understanding of the feature will help.
The Drive signal inputs by Default are enabled and when you use the enable feature what your actually doing is turning them off.
One of the main reasons to use the enable feature is so the Motor stays powered up. The enable signal just disables the drive inputs
and leaves motor under holding torque.

This is fine for Say limit triggers for when other axis need holding Ie Z axis and when leaving machine for any length of time when Mach is not Re-set so motors or axis can't accidentaly moved. But Not when in E-stop situation when really power should be removed from the drives.

fvfdrums
19-02-2015, 08:18 PM
Dean thanks, I am putting a fully latched safety circuit on the machine just could not get a good grasp of how the enable worked so thanks for that!

fvfdrums
25-02-2015, 08:23 PM
So whilst getting along with the electronics circuits I am going to start to fashion some machine guards to protect both me from the machine screws (I have a tendancy to get too close to the machinery - through no fault of my own) and also to stop flying chips and debris getting into the screws.

Whilst at that I want to run some ally channel so I can have the E chain run along side the guards, what size chain do people generally use for the various bits of the machine?

I can see at the moment I am likely to have:

z axis - spindle main cable, z axis limit and home switch and water pipes for spindle, z axis motor cable

y axis - All the above plus the y axis motor, y axis limit and home switch

x axis - all the above plus the x axis motor wire, x axis limit and home switch

Any suggestions on size?

I can get hold of up to about 50 x 20 from a local supplier but its pretty pricey p/m

njhussey
25-02-2015, 08:42 PM
It's generally a good idea to separate power from signal cables but that would mean 2 lots of e-chain...

routercnc
25-02-2015, 09:19 PM
I'd agree with separating power from signals
My machine has echain down either side of the X axis carrying each type.
The machine before this one has some of them together and tripped out quite a lot. The new one is much better but the long Z home cable occasionally still causes a trip.
I must point out that the previous machine and the current machine both use cables direct from the BOB so they end up being long especially Z. How much of this can be improved / removed further by using relays etc I will soon find out because that will be of my electrical upgrade in progress.
Back to your question. I started with 50mm or so but these are quite bulky so latest machine has something like 20-25mm width and is much more compact whilst still taking the cables. Helped by splitting runs down each side as mentioned.

fvfdrums
10-03-2015, 02:50 PM
Right,

I am about a week away from getting the control box wired up so I am just ordering some parts last min.

The PSU I have ordered is http://www.airlinktransformers.com/chassis_mounting_toroidal_transformers/chassis_mounting_toroidal_transformers_standard_ra nge/CM0625225/

I wanted to check if these parts are going to work ok with this coil.

Bridge Rec:http://www.ebay.co.uk/itm/KBPC3502-BRIDGE-RECTIFIER-35AMP-200V-/231452879829?pt=LH_DefaultDomain_3&var=&hash=item35e3aaabd5

Capacitor:http://uk.farnell.com/vishay-bc-components/mal210119223e3/cap-alu-elec-22000uf-100v-screw/dp/8820945#ProductSubstitutes

I know Rapid do a cheaper one as do Farnell however they have indicated it probably won't be back in stock for a good 10 days which is too long for whats planned in the diary!

If I am a mile out please let me know :)

Clive S
10-03-2015, 04:05 PM
Those bits are fine. But as you know the cap is a bit (lot) expensive. ..Clive

fvfdrums
10-03-2015, 05:32 PM
Many thanks Clive

I am searching around in the hope of finding them a bit cheaper but at least i am on the right track!

Cheers

njhussey
10-03-2015, 05:59 PM
You might find it cheaper to get multiple smaller caps, I got 4 x 4700uF ones for a few pounds each, just means more connections to make...

fvfdrums
10-03-2015, 06:39 PM
Also... what sort / size cable do people generally use for wiring coming from the psu to the stepper drives and wiring the power elements of the estop circuits bearing in mind I am using the CSMIO from cslabs so its all 24v in relation to the motion controller except the mains in

Just trying to get an idea of whats best to order in bulk

Clive S
10-03-2015, 07:36 PM
Also... what sort / size cable do people generally use for wiring coming from the psu to the stepper drives and wiring the power elements of the estop circuits bearing in mind I am using the CSMIO from cslabs so its all 24v in relation to the motion controller except the mains in

Just trying to get an idea of whats best to order in bulkYou could use cat5 flexi cable or a screened cable for all the switches and limits, Estop etc. 1.5mm CY 4 core for the steppers (don't forget to ground to a star point at the driver end) and a bit of 2 core from the 24V power supply to the BOB.

JAZZCNC
10-03-2015, 08:14 PM
Also... what sort / size cable do people generally use for wiring coming from the psu to the stepper drives and wiring the power elements of the estop circuits bearing in mind I am using the CSMIO from cslabs so its all 24v in relation to the motion controller except the mains in

Just trying to get an idea of whats best to order in bulk

You want Tri rated for general single wire runs for power to steppers, relays etc like this. http://www.csecables.com/acatalog/Tri-Rated-Cable.html#aTri_2d0_2d5

For signal cables you want Shielded CY cables or like Clive says you can use twisted pair Cat5 but only use inside control panel not running to limits etc on machine as it's not really flexible enough. I tend to use Cat5 in box as theres less wires and one cable will provide for 2 drives.
http://www.csecables.com/acatalog/CY-Cable.html

Bear in mind the Csmio doesn't provide voltage from the I/O you have to feed it 24V +/- to each I/O so you'll need plenty of connections on the 24V rail or do some jumpering. Suggest you get some Din rail terminals with Jumper bars to create one Multi connector.

fvfdrums
10-03-2015, 08:24 PM
Thanks Clive and Dean.

That tri rated cable what size am I am looking at for the stepper power feeds?

JAZZCNC
10-03-2015, 10:30 PM
Thanks Clive and Dean.

That tri rated cable what size am I am looking at for the stepper power feeds?

Well 0.5mm/2 would be ok on Max amp rating given most motors are rated around 4-5A but 0.75mm/2 will give plenty of safety margin if you'd prefer OTT. I think the Tri rated cable is safe to around 600Vdc so you no worries here.!!

Clive S
11-03-2015, 08:39 AM
For signal cables you want Shielded CY cables or like Clive says you can use twisted pair Cat5 but only use inside control panel not running to limits etc on machine as it's not really flexible enough. I tend to use Cat5 in box as theres less wires and one cable will provide for 2 drives. Yes quite correct I should have said cat5 flexi as in the patch cable type. (although you can buy flexi by the roll). Clive

Jonathan
11-03-2015, 11:06 AM
Aliexpress is your friend for cheap capacitors, and just about anything really:

http://www.aliexpress.com/wholesale?catId=0&initiative_id=AS_20150311020049&SearchText=10000uf+100v

You need to be wary of fakes - I got these (http://www.aliexpress.com/item/Electrolytic-capacitor-10000uf-100v-100v10000uf-35-50mm/1314627544.html) as they were the cheapest at the time and they're fine. On the lower end of the tolerance but that's not a big deal for what we're doing.

Jonathan
11-03-2015, 11:17 AM
[Tried to edit previous post to add this, but kept getting 'message too short' error]

This is how I've been using the capacitors:

http://www.mycncuk.com/attachment.php?attachmentid=14850&stc=1

It keeps things reasonably neat.

PAULRO
11-03-2015, 12:03 PM
I think if you go to '' GO Advanced '' you can over come the problem of '' message too short''

fvfdrums
11-03-2015, 06:23 PM
That's great thanks for all that, spent a small fortune on the control cabinets stuff today but it should all arrive in time. Went for 4 smaller caps in the end.

Today's stumbling block is the main belt for the x axis. Measured up and it needs to be 3000mm. I have spoken to a number of suppliers and none can do anything over 2500.

Would a welded polyurethane belt be ok? This looks like it might be the only way I can get one of these to work?

Any suggestions

njhussey
11-03-2015, 06:28 PM
How come 3000mm? Isn't your machine footprint 1200 x 900mm? My footprint is 1300 x 950mm and I'm using 2525mm long belt.

Can you not use one belt between the X axis ballscrews and then with a double pulley on one ballscrew just put a short belt to the stepper?

fvfdrums
11-03-2015, 07:04 PM
No the width of the machine now is around 1300 between x axis screws

fvfdrums
11-03-2015, 07:12 PM
The problem I have with that and the reason I wanted the one belt is mainly because if the long belt snaps the short one will still be driving one axis.

I'd have just slaved them otherwise :/

JAZZCNC
11-03-2015, 07:31 PM
Would a welded polyurethane belt be ok? This looks like it might be the only way I can get one of these to work?

If your talking about buying a welded belt not knocking one up your self then yes they work fine. My old machine was 3200 with made up belt and never had any problems. In over 5yrs only had to change one belt after pulley fell off which was my own fault.

fvfdrums
11-03-2015, 07:34 PM
Yeah I have no intention of welding it myself :)

It's from a belting supplier, thanks for confirming that Dean.

JAZZCNC
11-03-2015, 07:34 PM
The problem I have with that and the reason I wanted the one belt is mainly because if the long belt snaps the short one will still be driving one axis.

I'd have just slaved them otherwise :/

Not a problem either just put a sensor on longer belt which is tied into E-stop so if it snaps machine stops.!! . . . . I did this with my machine just because I leave it unattended for long periods.

Lee Roberts
12-03-2015, 12:17 AM
I've got a load of new old stock of screened 8, 6 and 4 core alarm cable if anyone needs any, it's worth about 15 a drum on the bay but I can't be asked with that, happy to help anyone out if they would like some.

Should be good for limits and so on?

.Me

fvfdrums
12-03-2015, 03:50 PM
right I have got the belt! well its ordered, cost a small fortune mind so I hope it won't break!

Yet another question. I am just fitting up the limit switches on the machine and then the homing.

I have the large industrial style limit switches with a roller that can be activated either cw/cww which I am going to have activated by a ramp rather than bumping into it. However the homing switches are proximity. how and where do people generally fit these?

JAZZCNC
12-03-2015, 07:57 PM
I have the large industrial style limit switches with a roller that can be activated either cw/cww which I am going to have activated by a ramp rather than bumping into it. However the homing switches are proximity. how and where do people generally fit these?

This going to sound obvious when I say it.!! . . . . Where ever you want HOME to be.!!

Generally you'll position them so they follow Cartasian coordinates ie Bottom left corner and in front of the limits but they can be any where you like. They are really only used as a Fixed referance point to define MACHINE coordinate Zero which you then use to Reference WORK coordinates.

One problem with NOT putting them in corner is that depending on which side of the switch axis is parked it could miss the switch. This is why generally you put them in a corner and set controller up so it always HOMES negative or Positive so can't miss the switch.

fvfdrums
13-03-2015, 09:33 AM
It was more how they were positioned however I think I have figured the best solution(s) for this machine based on keeping them out of the way of the "crap" thats likely to be thrown up at them if mounted lower down.

Managed to get them all as travelling switches as I had hoped so should make for less wires everywhere.

It makes sense you would home at the front I suppose, I dont know why but I thought to start with if you were standing at the front it would be back of the machine left hand side, but I suppose thats due to the way my machine is positioned. Although it does still give good access to tool changing etc hmmm I will have a think.

Thanks though Dean

JAZZCNC
13-03-2015, 12:40 PM
It makes sense you would home at the front I suppose, I dont know why but I thought to start with if you were standing at the front it would be back of the machine left hand side, but I suppose thats due to the way my machine is positioned. Although it does still give good access to tool changing etc hmmm I will have a think.

Depends really where you stand at the machine. Often routers are viewed from the side in which case viewing from the front it would be back left corner and long axis woul'd be X axis. Viewing from the side that would still be bottom left corner.!

If you stand in front of machine then you'd call across the gantry the X axis and long Axis would be Y. Again this would follow typical drawing coordinates.

But like I say doesn't have to be and some don't have it this way. I prefer so home is in bottom left corner and all moves in MACHINE coordiantes are positive. So Homing is always traveling towards negative.

routercnc
13-03-2015, 04:16 PM
Hi Paulo
I bet when you started this thread you didn't realise that the title '
On the horizon' would be so apt! First post is nearly 3 years old . . .
On a more helpful note you mention home location and tool changing - don't let one dictate the other as you can set a PARK position at any arbitrary point you want. Mach3 2010 screenset has this built in or you can add the feature to the standard screen if I remember correctly.

Neale
13-03-2015, 04:27 PM
I don't even like people talking about front and side - I'm not sure which is which! I'm sure opinions differ... For me, the long axis is X and short, gantry, axis is Y. Already we have upset the north American community who tend to use the opposite convention. I stand facing the long side with the gantry home position to my left and which makes the LH corner nearest me the natural 0,0 place. Feels right as well as it matches the usual axis layout you would see in a graph. It also means that the spindle is close to hand for tool-changing when it's in the home position. But as long as you know how your CAD/CAM process maps to the bed of your machine, this is all a bit arbitrary and you can decide for yourself which axis is X and so on, and what's convenient for home switch positions.

JAZZCNC
13-03-2015, 08:17 PM
On a more helpful note you mention home location and tool changing - don't let one dictate the other as you can set a PARK position at any arbitrary point you want. Mach3 2010 screenset has this built in or you can add the feature to the standard screen if I remember correctly.

Agreed and just to add to this 2010 screen set actually has a TC (tool change) position and a Park position. In practice you'll change tools anywhere you feel suits you best and it probably won't be in one set location.
Many don't realise you can actually jog away to any point to change tools so often you'll just jog closest location to you from work piece and change tool there. Running to the other end of even a medium size machine to change tools soon becomes tiresome, so nearer to the Work location the better.

This fits and brings nicely to placing work piece on the table.? Again on medium to large routers you'll often be cutting pieces much smaller than the table size and it's tempting to always locate in same place which is easy to reach.!! . . . This is not good for the machine as it tends to wear screws and rails etc in one place more than another so spread the work around the table. This is when you'll want to jog to closest location to workpiece rather than run to other end of machine for each tool change.

JAZZCNC
13-03-2015, 08:26 PM
I don't even like people talking about front and side - I'm not sure which is which! I'm sure opinions differ... For me, the long axis is X and short, gantry, axis is Y.

Easy really.! Side is when gantry is running side to side. Front is when Gantry is running away and towards you.

If stood in front then you want the Axis which runs across the Gantry to be called (X Axis) and the Gantry moving away/towards you (Y axis) This way you retain the Cartaisian coordinate system with X0,Y0 in bottom left corner.

There is No right or Wrong only preference. Mostly based on where you stand or view.

Neale
13-03-2015, 11:12 PM
Side is when gantry is running side to side.

That's why I find this whole front/side business confusing - should that have said when gantry is running front to back, that is, left to right? I call the long side of my machine the front because that is where I stand to use it. Doubt if it makes sense to anyone else, as it's because of the layout of my workshop. But I strongly agree that it's just a matter of preference, and what is absolutely vital is that x0,y0 is at the lh corner nearest you, so the bed looks just like the virtual sheet of paper you draw on in your CAD programme. If you don't, you are going to confuse yourself every time you try to set up a new piece of work. I've ended up with x0,y0 at the far right-hand corner of my 3D printer and I get mildly baffled every time I use it. I should just turn it through 180 deg, but I'm too lazy to shunt everything around to do it.

JAZZCNC
14-03-2015, 01:22 AM
That's why I find this whole front/side business confusing - should that have said when gantry is running front to back, that is, left to right? I call the long side of my machine the front because that is where I stand to use it.

Well it's down to how we typicly define a router I suppose.!! Look at any picture of a router, DIY or Industrial and 99% will show it looking length ways down the narrow view of machine directly facing the gantry. This facing the gantry would be classed as the Front and the Gantry would move away and towards you.

If your stood facing the long side you'll be looking side ways down gantry length and it would indeed move left to right or side to side as I put it.

fvfdrums
15-03-2015, 01:47 PM
http://tapatalk.imageshack.com/v2/15/03/15/f95a70723d948f9c6de5a3a498f2ba77.jpg

One of many things that's arrived this week. Exceptionally well made and presented. If it operates even half as good as it looks (which I have no doubt it will) I'll be very happy!

njhussey
15-03-2015, 02:17 PM
I got a couple of those in the last couple of weeks (one for my router and one for the planned mill conversion) they are nicely packed and presented, im just reading through the instruction manual at the moment...

fvfdrums
15-03-2015, 04:16 PM
Yeah I am pleased,

Have this week set aside to finish up the general mechanics of the machine (to an basic operating stage) then fri-sun to wire up the panel and get it all working so fingers crossed

njhussey
15-03-2015, 10:39 PM
A similar timetable to myself except mine will just be done in the week, I've only got a couple of bits to do mechanically and then the rest is all electrical...

fvfdrums
16-03-2015, 09:38 PM
Belt arrived today.....

......wrong size. Anyway after a long time on the phone and knowing they were not really interested in helping out "small orders" I decided to just move the x axis motor to accommodate it. Turns out it's worked out quite well but what a pain this belt had been! Anyway it seems to be fine now.

Most of the electrical stuff has arrived now only waiting on a few bits and the e chain.

Should have moved on a lot by this time next week fingers crossed.

fvfdrums
16-03-2015, 09:39 PM
Also.....

Planning on using grub screws on the steppers at 90 degrees to each other. What size would people use on an 8mm shaft and a 10mm shaft?

njhussey
16-03-2015, 09:44 PM
Also.....

Planning on using grub screws on the steppers at 90 degrees to each other. What size would people use on an 8mm shaft and a 10mm shaft?
Depends on the size of the pulleys I guess, I've used M4's on the 20 tooth pulleys as well as the 40 tooth ones. My 40mm pulleys are a push fit on the ballscrews so I'm hoping that's enough. Could always put a bit of loctite on too...

fvfdrums
16-03-2015, 09:48 PM
Well I'm on 30 tooth pulleys. So I'm guessing that would work as well. I have a similar fit with the pulleys so that should work. Cheers

Clive S
16-03-2015, 10:24 PM
Well I'm on 30 tooth pulleys. So I'm guessing that would work as well. I have a similar fit with the pulleys so that should work. CheersHammer a bit of 1.5mm copper wire flat and cut a small piece off to drop down the hole where the grub screw goes I find it make a big difference and does not mark the shaft. Clive

JAZZCNC
16-03-2015, 11:01 PM
Depends on the size of the pulleys I guess, I've used M4's on the 20 tooth pulleys as well as the 40 tooth ones. My 40mm pulleys are a push fit on the ballscrews so I'm hoping that's enough. Could always put a bit of loctite on too...

Larger grub screws the better so can get good purchase on them, fiddley Grub screws are a pain and definately loctite the pulleys on. You'll never really want them off again other than to replace and certainly don't want them spinning on the shaft. Also mark them so for easy visual reference so can check they are not spinning.

Boyan Silyavski
17-03-2015, 06:49 PM
I did like Dean says, larger grub screws. I also filed flat recess on shafts, where grub screws go. It was quite easy using small square file. It seemed to me it would help. Locktite also. In fact my major mistake on the first build was not using locktite on all screws. Result was from vibrations or whatever at least 2 screws difficult to access
loosened so i wasted some time tightening again all screws on my friends machine. On my current build i use Locktite on all screws and i hope all will be perfect long time after i am finished. Same goes for the supported rails. When all was mounted and square, i carefully poured locktite between screws and rails. later checked it, it worked. Then i fit the plastic caps.

fvfdrums
18-03-2015, 03:59 PM
Thanks for all that info guys very helpful. I can just about get away with2 m4 grub screws on these pulleys so that's the way I'll go.

Half finished up one side cover just waiting on some bits to arrive. I figured if I didn't do it now once the machine was running I would probably keep putting it off!

http://tapatalk.imageshack.com/v2/15/03/18/d16769582e06f1f53ed4c0dfb5cbaa24.jpghttp://tapatalk.imageshack.com/v2/15/03/18/440b7ade5225bdc4c1cc1071207690d4.jpghttp://tapatalk.imageshack.com/v2/15/03/18/977e79cc44e292b008476bd1829d6180.jpg

njhussey
18-03-2015, 08:59 PM
I was looking at a way of protecting the ballscrew and was thinking of C section Ali but couldn't see how I was going to put the brush on the rail side to seal the gap. How are you doing it as I can't see a brush so I guess chips etc could still get in there?

fvfdrums
18-03-2015, 09:28 PM
As I mentioned it's half finished. If you look there is a brush on the outside edge, I did try a 2" brush from one side but it was too much so opted for 2 1" brushes. The other just sits off from the bearing rails on the inside of the gantry so the two pretty much meet in the middle.

njhussey
18-03-2015, 09:35 PM
So you did....I must have glossed over that bit! How are you fixing it by the rails? Looking forward to seeing it finished...

fvfdrums
18-03-2015, 09:40 PM
The brush sections fit neatly under the bearings with enough clearance for some countersunk m5 screws to hold it down along the full run. Just haven't got round to that yet.

fvfdrums
18-03-2015, 09:41 PM
Btw tool station are pretty good price wise on these brushes.

njhussey
18-03-2015, 09:41 PM
Where did you get your brush strip from, how thick is it?

I wasn't quick enough!!!

fvfdrums
20-03-2015, 09:53 PM
Right we are wiring up the psu. Transformer wired correctly giving 52 Vac. Connected to the Bridge rec at correct terminals. Output from the rectifier on the dc terminals is 45v ?? Shouldn't this be 70ish? Do we have a broken rectifier?

Jonathan
20-03-2015, 10:04 PM
Have you put the capacitor(s) on the output of the rectifier? If not then that reading seems about right, as the meter is reading the rectified AC waveform, not a smooth DC output.

fvfdrums
20-03-2015, 11:04 PM
Thanks Jonathan,

so we have now connected the caps up to the BR, on powering up to check what voltage we were getting instead of even getting there we got a huge amount of humming and some extreme heat through the negative cable coming from the BR so immediately turned it off.

any ideas what could be going on / we are doing wrong?

we have checked that it is definitely the +ve of the BR going to the +ve on the caps and the same for the -ve.

does there need to be a load on the PSU before we power it up?

fvfdrums
20-03-2015, 11:36 PM
scratch that - problem solved, 68/69 Vdc now :)

njhussey
20-03-2015, 11:39 PM
What was it?

fvfdrums
21-03-2015, 12:31 AM
well, it was only one cap doing the crackling and humming so changed it out and works fine now so I think it may have been a dodgy one!

Clive S
21-03-2015, 01:43 AM
well, it was only one cap doing the crackling and humming so changed it out and works fine now so I think it may have been a dodgy one!or connected the wrong way round:nonchalance: ..Clive

fvfdrums
22-03-2015, 09:51 PM
So got movement on y and z today :)

However need some assistance with the csmio board.

We have one digital input set up. Input 0 (pin 1. +ve, pin 14 -ve)

Feed runs from 24v supply through t3/l3 on contactor to pin 1, 24v present on pin 1 measured with MM.

And pin 14 connected to 24v -ve.

In Mach ports and pins estop is enabled, port #10 and PIN number 0 or 1 we have tried both and active high and low tried and with no combination of these can we get a response from Mach or an LED on the unit in either state

What are we doing wrong??

Other than that it's awesome to finally have some movement!!

JAZZCNC
22-03-2015, 10:06 PM
Well you are connected correctly with right port and pins so Just has a test of the input try running 24V direct to pin 1 not thru contactor. It should light the Led on the controller. (you can also open plug-in to see active I/O state it's often easier)

JAZZCNC
22-03-2015, 10:12 PM
What is the contact type NO or NC.! . . . . If NC then you want E-stop Pin active High and vise versa if NO.

fvfdrums
23-03-2015, 01:00 AM
Problem solved, one wire going into a din connector was clamped on the insulation and not connecting, after that works fine so thanks.

Finally..... The relay outputs from the csmio - to control the spindle forward control from Mach should it just be wired from DCM on huanyang inv to pin 25 and pin 12 to For? That's for relay output 4 I'm hoping? I've got the analog hooked up fine just can't get it to switch on. I've set the parameters as well so it's not manual control pd001&2 I think (not in front of the machine right now)

JAZZCNC
23-03-2015, 01:23 AM
Finally..... The relay outputs from the csmio - to control the spindle forward control from Mach should it just be wired from DCM on huanyang inv to pin 25 and pin 12 to For? That's for relay output 4 I'm hoping? I've got the analog hooked up fine just can't get it to switch on. I've set the parameters as well so it's not manual control pd001&2 I think (not in front of the machine right now)

Yes wiring correct but you need to go into ports & pins and spindle setup then Spindle control and check the disable Relays box and set M3 to output #4.

JAZZCNC
23-03-2015, 01:34 AM
Just as a heads up as it's common Gotcha.!! . . . One thing to watch for with these Controllers is you need to check your drives are using the same Step edge otherwise you'll lose a step on every direction change.
The IP-M is set to leading edge so check what the drive is set to.? Can't remember what drives your using and can't be arsed to go back searching but if AM882 or EM drives then you can change the Active edge in software and possibly using Dip switches but can't remember.
Some drives don't give this option but it's not a problem as you can just change the Active edge state in Motor outputs. Thou it doesn't work in usual way Mach3 does and reverses motor direction so if you need to reverse motor direction then use "Reversed" in Homing limits.

Best thing is to test by righting some g-code with lots of Back n forth moves and check the axis returns to same spot.

fvfdrums
23-03-2015, 12:48 PM
http://tapatalk.imageshack.com/v2/15/03/23/fd3eea7ca4e2d91f28d850e9f96f10e4.jpg

When you say check the disable relays do you mean put a tick in the box or check it's not ticked?

The csmio manual suggested it should be unticked.

However tried it both ways and it still doesn't work.

I have 24v across DCM and For at the inverter. And 24v at pins 25/12

Output 4 light comes on but no action. Have I missed something in the inverter settings :/

Sorry bit lost now

fvfdrums
23-03-2015, 01:24 PM
Slight follow up, if I send a m3s2000 command then I put the multimeter across the 25/12 pins the spindle powers up so the analog is working but it appears neither of the relays in the csmio are switching even though the little leds light. I'm going to try a separate relay with and output from 1-3 ( I'll make sure I supply the 24v to the board for those outputs) and

JAZZCNC
23-03-2015, 01:26 PM
Ye sorry my fault worded it wrong should have said make sure un-ticked.

Sorry about this but I know what your problem is but must have had brain failure.!!! . . . . . . In ports n pins set the out put your using for spindle to Pin 4 not pin 12.!! . . . . It's a cock up in the manual and to make it worse I was the one who told CSlabs about it so should have known better.!!

For instance if you set M3 in spindle control to output #1 then go into outputs and set output #1 to pin4.

fvfdrums
23-03-2015, 01:43 PM
Cheers again Dean however we figured the pin thing out from the estop settings as someone else online mentioned the pins related to the output number not the pin manual.

So in doing all this the output 4 "Pin" has always read 4 and 5 has read 5 when testing this. The only mention of 12 was where I was wiring to.

I don't know why but I've got a feeling these relays are not working :/

I'm going to nip out and get a din relay and try the outputs 1-3 to try and get it to work for now

JAZZCNC
23-03-2015, 01:51 PM
Try what I said set OUTPUT #1 pin 4 and then in spindle control set M3 #1 . . . And see if it works. That's how I set the spindles with IP-M.

fvfdrums
23-03-2015, 02:29 PM
Well I gave it a try and still nothing :/ pics below are the settings and you can see output 4 is coming on....

http://tapatalk.imageshack.com/v2/15/03/23/82307559d83ce5e57e9af60a054480b5.jpg

http://tapatalk.imageshack.com/v2/15/03/23/180f3ac29486c4b607fcf1ce307cd227.jpg

http://tapatalk.imageshack.com/v2/15/03/23/bdca860720ada4f70c2ee659d1836301.jpg

JAZZCNC
23-03-2015, 02:56 PM
I'm presuming you have turned the Analog Spindle DAC on in Config Plug-in.?

Output 4 is obviously working as it's LED is lighting so just put a continuity test across the pins and it should toggle ON/OFF.

Aftet that then I'm at loss to help from a far.!! . . . . I'd be very surprised if the controller is faulty but suppose it's possible thou would be a first to me and I've fitted a fair few now.!

fvfdrums
23-03-2015, 03:05 PM
Right thanks for all the help Dean.

In answer to the questions:

Yes DAC turned on in plugin.

Did continuity test, get nothing between pins when they are on or off.

Have just wired up a din relay to output 1 from the csmio and got it working first time no problem. So who knows but I'm happy with that

The only thing that's not working quite right is the rpm if i set it at 2000 or 1000 it spins the same speed. Analog signal is fluctuating as expected with the different s commands so I think I've probably not set something right on the inverter parameters?

JAZZCNC
23-03-2015, 04:18 PM
Have just wired up a din relay to output 1 from the csmio and got it working first time no problem. So who knows but I'm happy with that

Wants returning then has it should work.!

fvfdrums
23-03-2015, 06:07 PM
How many poles should this 3kw motor have? My inverter defaults to 4 but I I'm seeing 2 a lot on the 2.2kw versions?!?

fvfdrums
23-03-2015, 09:05 PM
Well the checklist is getting smaller..... For now anyway.

X axis still needs wiring in and limits and home need wiring as well but it's all coming along.

Thanks again for those who have been answering the multitude of questions over the last few weeks

http://tapatalk.imageshack.com/v2/15/03/23/c3cfa24c3ecb7cd36c0a74eb8d0dad2d.jpg

http://tapatalk.imageshack.com/v2/15/03/23/8cdd295322d92640a0641652457d944c.jpg

http://tapatalk.imageshack.com/v2/15/03/23/a5d5413dcedb17b6f2e121858fa94b0e.jpg

http://tapatalk.imageshack.com/v2/15/03/23/783ae5e273b5efcdd160ea25f69760e9.jpg

http://tapatalk.imageshack.com/v2/15/03/23/3fb41da4ea24edc3b50eb9bd9468b77e.jpg

Noplace
24-03-2015, 08:20 AM
Hi I just want to say this is one neat build!

If you don't mind I'm in the process of designing my gantry and would like to borrow some ideas from your design, would you mind showing the gantry from the back and how you connect the ballscrew to the Z plate

thanks

Gotty101
24-03-2015, 10:50 AM
Loving the build. Just a quick question though. Where did you get the grey conduit that the cables run in with the slots in it? I have no idea what its called.

Thanks

Trev

fvfdrums
24-03-2015, 11:00 AM
@Noplace.... Thanks, the gantry was based off a design Jazz (dean) put up quite a while back so can't take all the credit for that. I'm not with the machine at the mo but I'll try and take some pics when I get back.

Gotta.... I searched cable trunking. If you search chalon components on Google go to their website and then look under the cable management section its in there.

JAZZCNC
24-03-2015, 04:27 PM
@Noplace.... Thanks, the gantry was based off a design Jazz (dean) put up quite a while back so can't take all the credit

YES you can take Credit because you have done my design proud so take the Bow my friend you deserve it.. .:encouragement::applause::victorious:

Put an E-stop on the gantry or Machine thou because believe me when the Shit hits Fan you'll never reach that E-stop on cabinet before damage is done.!! . . Even when close to hand it's mostly done and dusted for work piece in blink of an eye but at least you have half chance of saving the tool but up there on wall you'll never get to it in time before tools is lost or work piece ripped off the Bed.!!

GEOFFREY
24-03-2015, 04:47 PM
Your machine looks great. Well done. G.

fvfdrums
24-03-2015, 05:41 PM
Thanks Dean I appreciate that :D although without yours and others assistance along the way I probably wouldn't have had half the machine I have now. Must not get ahead of myself still a way to go!

Yes agreed we both looked at the machine after wiring it and can see two potential spots for an additional e stop button - I used to have what I call e stop blindness when running the huge 3 axis lathe I used to have, when I got the odd decimal in the wrong place (all code was written in note pad none of this cam :/) and the machine would try and turn the chuck quite successfully I could never see the big red button for panic!!

fvfdrums
24-03-2015, 05:55 PM
Any suggestions on chip control? and how to catch the little buggers? I have been looking at venturi vacuum systems etc but was not sure how much they will effectively collect? as I am pretty sure an industrial style wet vac with a cyclone separater would be fine for wood but have very little effect with aluminium chips? I could be wrong?

I was thinking of having a few air heads running off the compressor to a ring which can be mounted like a dust shoe near the spindle head with a couple of adjustable spouts to randomly blast short sharp bursts of air from different directions to try and clear the chips from the cut, might this work? combined with some sort of fogger system

JAZZCNC
24-03-2015, 10:21 PM
Wood is easy just get a good vacuum on the job and it's sorted.! . . . BUT Aluminium is another story.!!!

Air works good for clearing but it blasts those little buggers all over the place. Fogger or Mister will choke you to death unless machines enclosed so I'd forget typical fogger system. What You need is Odour-Less Fogger that spits little droplets at the work and doesn't create mist, this works good.

BUT I'll warn you coolant (or indeed Air) don't mix well with wood. Coolant turns wood dust into very abrasive paste that is a twat to clean and wears machine like crazy.
If your planning on cutting wood and Ali then I'd stick with air for cutting Ali and don't use coolant.

Boyan Silyavski
25-03-2015, 12:12 AM
With the risk of sounding a bit biased, cause right now i am designing and testing my own Fogless Mister Cooling, see post 5 (http://www.mycncuk.com/threads/8061-Fogless-Mister-Systems?p=68212#post68212) there, i would say that to have such a system is Godsend thing.

Want only to blow away chips and cool by air? Then the perfect air stream will do the job, aluminum,brass,other metal or stone- let some liquid in the stream. Cheap to run, low on coolant per hour :whistle:


I mean is one thing to blow air over the bit its another thing to blow a precise air stream.


PS. Dean, expect soon a free sample of the nozzle , cause i would not think that i have achieved it, without you saying that is ok and works under all possible scenarios. :beer: