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charlieuk
10-02-2014, 02:48 PM
Just started building 3 aixis cnc aprox 20' x 3' x 2' I am building it from 80mm aluminium extrusion and using a 20mm hywin rail system on all 3 axis with rack and pinion on x and y and a ball screw on the Z. It is a cantilever arm style machine and will mainly be used for cutting foam and other reactively soft materials.

The aluminium i have purchased from KJN and the motion control and linear movement parts are being supplied by CNC4YOU who have been exceedingly helpful and a great bunch of guys.

It is still at very early stages but i do have a few pics of the frame coming together which i will post a little latter. I look forward to any feed back or advice.

charlieuk
10-02-2014, 07:02 PM
heres the first few pics

charlieuk
11-02-2014, 11:29 PM
the frame is almost together although it was pretty expensive i think the ease of construction and accuracy has more than paid for itself plus it would be a lot easier to move if i ever need to.

bikepete
12-02-2014, 12:29 PM
As no other replies yet just thought I'd say thanks for posting and please keep it up - watching with interest - should be an awesome huge machine when done :-)

charlieuk
12-02-2014, 02:15 PM
no worries, the frame is all locked in solid and started on the gantry. just figuring out bolting the rails down. From what i have read on the hiwin site for the RG20 rail its saying M5 bolts which appear to be a little small in the rail holes but i gees that leaves room for fine adjustment? is bolt them down every 180mm sufficient or do i need to do it more like every 120mm?

Lee Roberts
12-02-2014, 02:29 PM
Wow Charlie what a build this is going to be!

The rails come pre-drilled so you would want to bolt them down using those fixing distances, I dont want to say to much because I dont know what you have planed but it reads as though you are going to bolt the rail directly to the extrusion?

Edit: Just re-read your first post "soft materials".

.Me

charlieuk
12-02-2014, 02:47 PM
the rails are pre drilled every 60 mm but have been told that i could probably bolt them less hence possibly going less. The hardest thing i will be machining will be ply wood but mainly 90% of the work will be foam. The rail is going directly on the extrusion which is 80X80 ali and using the centring t blocks. More than happy to listen to any other suggestions, i am basically just going by what i have seen on similar machines that have been built with the same intended use.

many thanks charlie

bikepete
12-02-2014, 02:47 PM
Presumably the rails are drilled at the standard 60mm spacing... guess that could get tedious over 20 feet/6m - approx 100 per rail... but only needs to be done once. Guess you might get away with every other hole (120 mm) but doing them all would add a little to rigidity I would think...

Did you find the Hiwin rail in 6 m lengths BTW or are you going to have to butt two lengths up together? Longest I've seen is 4 m at e.g. WMH Transmissions Ltd - Product List - HGR 20 GUIDE RAIL<BR><BR>PITCH 60<BR><BR>NORMAL GRADE (http://www.wmh-trans.co.uk/Products/HGR_20_GUIDE_RAIL_PITCH_60_NORMAL_GRADE)

charlieuk
12-02-2014, 06:04 PM
no the max length is 4 meters so would have to have a joint , the cheapest i could get was a max length of 2.7m so would need 2 joints which i have ended up with however using 3 two meter lengths for each rail. We have spoken with hiwin and they have said it is fine to just but them up together without anything else.

bikepete
12-02-2014, 06:30 PM
Would definitely bolt every 60 mm then as the last thing you want is anything moving once you've got all the joints perfectly aligned.

charlieuk
12-02-2014, 08:30 PM
cheers thanks for the advice best order a stack load more slide blocks then mounting is no sweat as i can put them on to the rail and then just slide it strait on to the aluminium. Next job i think is to make sure it is all perfectly level on the floor and get a plate made up to bolt the carriages too. If i can get the plates laser or water jet cut do you think i can rely on there accuracy to get the two carriages to aline or do i need to factor in adjustment with a oval hole or something?

many thanks again

charlieuk
07-03-2014, 11:50 AM
been working on modifying the design a little bit to try and simplify the build as its my first. I have just got the parts to build the z axis however annoyingly the mounting holes on the bearing blocks are not spaced the same as the ali extrusion so i am assuming the best way to solve this is by having some plates made up to go between and allow me to bolt one to the other?

routercnc
07-03-2014, 10:33 PM
This is not unusual. I think you are suggesting adding a plate under the bearing block to bolt to, which is in turn bolted to the extrusion rails. This is fine, but will raise your ballscrew by the thickness of the plate - is that a problem?

If it is a problem, these blocks normally have both vertical holes and horizontal holes for mounting. So instead you can use the horizontal holes to bolt into a thick plate/block which is next to the bearing block, and is in turn then bolted vertically down onto the extrusion. The trade-off this time is a small loss of ballscrew travel equal to the thickness of the block/plate.

If none of these options work, you can drill and tap straight into the face of the extrusion (i.e not using the rails) - but you will need to check if there is enough material to tap into and you avoid the slots.

charlieuk
07-03-2014, 11:23 PM
yes that was what i had in mind.They do have horizontal holes but i am going to have to get the parts made for me so flat plates may be easier. i was wondering if i could bolt it directly but the holes are right on the edge of the slots so it would only be going properly through the very middle of the extrushion.

i have not chosen any steppers yet but was just wondering if i was going to need a reduction with belts and pulley that i plan on the top or wether normally it is just 1 to 1. the plan is to use a 2.2kw spindle and then there will be the weight of what is in the picture and what ever stepper i use.

charlieuk
11-03-2014, 10:06 PM
..............

charlieuk
11-03-2014, 10:23 PM
a few more pics

charlieuk
14-03-2014, 09:05 PM
...........

routercnc
14-03-2014, 10:07 PM
Charlie,

It's a very unusual machine and I can't quite work out which bit will be which, so the question you've asked about motor sizes is probably proving difficult for anyone to answer.

But be aware that you can move a fair amount of weight with a 3Nm Nema 23 if you give it enough voltage as the ballscrew gives you lots of mechanical advantage. Don't rush out and buy 34's until you posted the final design sketch of the finished moving parts as you'll get a more definitive answer.

Your earlier question about pulley ratio on Z is also tricky since your Z appears to be quite long. Lots of designs are just 1:1 on a 1605 ballscrew for Z. But your travel (if I read the design right!) is quite long so this mught not be your best option. Again, a picture of the overall finished design would get a better answer from the forum on that question.

The wooden template motor bracket looks OK as a concept (assume ~20mm ali in the finished design?). Probably get away without triangulating back to the extrusion. But you'll probably need to recess the underside of the motor mounting area to raise the stepper and leave enough shaft sticking out the top. Also the ballscrew end might also need some pocketing on the top to clear the pulley / grub screw access.

charlieuk
15-03-2014, 12:43 AM
I dont have any 3d drawings at the moment i tried to get sketchup to load on my mac but it didnt like it.

If you take a look at thins video it shows something similar to what i am building however i just have the flat table and i have decided to have the two beams coming out on the gantry rather than one so as to stiffen it up and split the two rails apart, then the z axis will go inside the square frame you see on the top in my picture.

the z is quite long i wanted to get as much as posable to be able to work on large block of poly styrene and by large i mean i buy it in 16' x 4' x 2' blocks so should i have aprox 500mm of z travel when done.

the plan is to get all axis bolted up and rolling before getting the motors which hopefully wont be too long, im hoping to get the plates for all the carriages this week. I wasn't to sure how thick the motor mount for the z was going to need to be, i was thinking only 10mm as i didnt think there would be to much load on it using a ball screw but happy to take advice on that and as you say ether recess the some of the areas to get the pulleys on or extend the shaft if that is posable?

many thanks Charlie

routercnc
16-03-2014, 09:48 AM
That makes more sense now in terms of the final design. Should have guessed with the O'Neil logo on the wall.

I think 10mm motor plate would also be OK stiffness-wise. What you will need to watch out for is if the bolt heads hit the belt then they will also need to be recessed. M8 cap heads would need 8mm depth of pocket so 10mm plate is then a bit thin.

In terms of recess or pockets for the motor - if you can find the drawings for the motors you might use you can check the length of the shaft. They are not usually that long plus you need access to the grub screw at the base of the pulley so that often means a pocket is required.

The motor plate extends past the extrusion and over the ballscrew - is that bit required? Are you hoping to bolt it to the bearing block as well? If not, you could cut it short and give more space for the pulley on the ballscrew. Just some thoughts . . .

charlieuk
16-03-2014, 10:17 AM
cheers many thanks for the reply, yes one of the things i will be cutting is stand up paddle boards but hope to use it for ply would and other things which is why i wanted the table. I see the problem about the bolts, i will have a look in to that one i would have thought i can come up with something there. I have just been trying to keep all the bits i am having to get fabricated as simple as posable as i only have a basic lathe and no milling capabilities so just getting it all laser cut.

i was wondering about using the block to bolt to as well there probably is no need really and possibly not posable as there is all so a plate having to go under it. If i actually could find a large bit of 90deg angle aluminium i could possibly use that for the motor mount and bolt it straight to the side of the z axis rather than the end.

many thanks for the advice! charlie

charlieuk
16-03-2014, 10:21 AM
something like this but would have to see what size motor i need and if it would fit.

Aluminium Angle from 2.5" to 100mm many thicknesses and lengths cutting service | eBay (http://www.ebay.co.uk/itm/Aluminium-Angle-from-2-5-to-100mm-many-thicknesses-and-lengths-cutting-service-/151080488638?pt=UK_BOI_Metalworking_Milling_Weldin g_Metalworking_Supplies_ET&var=450190796498&hash=item232d194ebe)


sorry the link didnt properly work they do a 9.5mm thick by 76.2mm deep option

Jonathan
16-03-2014, 01:12 PM
cheers many thanks for the reply, yes one of the things i will be cutting is stand up paddle boards but hope to use it for ply would and other things

If you want to cut plywood at all seriously, then I'd be concerned about the strength of your cantilevered gantry design. The cutting force for polystyrene is practically zero, so you can get away with a very weak gantry, but that's not the case for plywood.

Also, for the axis on the gantry (Y-axis?) your bearings are quite close together on the rails compared to the spacing of the rails, so I would be inclined to drive it with one ballscrew on each side, or at the very least make sure the ballscrew is centred between the two rails. The problem with the former is the ballscrew would intersect the Z-axis, so there may not be space for it. If you put a single ballscrew on one side the bearings on the other side will deflect more (i.e. it will rack like a typical CNC router gantry), so the obvious solution is to use two ballscrews. That's quite expensive though so you may want to just try it and see, but keep in mind the possibility of adding another. You could also increase the bearing spacing. It's hard to say for certain as it's difficult to discern which parts of the machine have the lowest stiffness and thus which parts should be improved if you want to cut plywood efficiently.

JAZZCNC
16-03-2014, 11:11 PM
Agree with Jonathan about being better to use twin screws for Y axis and to some degree that Z axis will be weak for cutting plywood but with just a simple change it could be made stronger to the point it would manage be ok.
It would cost more due to extra components and ballscrew placement wouldn't be the ideal but would stiffen things up enough. I've quickly thrown together a model to show you what I mean.
Obviously I don't know the spacing etc in side the Y axis frame or how you plan to attach the bearings and what spacing but looking at your pics I think there'd be enough room.? Spindle is just there for affect and the real thing would need extra support.

charlieuk
16-03-2014, 11:31 PM
thanks for that jazz i can see what you are saying and we did wonder about the third set of blocks and there is plenty of room to fit it all in and i have made the y frame so i can slide one side in to be what ever size it needs.

i was wondering about using 60x60 or 80x80 for the z axis but the 40x80 in a relatively short length seams crazy strong as it is.

i guess what i will do it try and get the x and y rolling and see how that feels and with the way it is i can pretty much just add to it if does look like its not going to be up to the job. I was planing on using rack and pinion for y could i just run a second motor on the other side rather than a ball screw? or possibly even one motor with a shaft and pinion on ether end like a car axel, although that maybe a little more tricky to build

if needed i could actually make the hole gantry narrower if needed just buy shortening a few bits if it would help.


I should say that i am not after crazy speeds for cutting ply or accuracy for that matter as it will be just for stuff that i would normally make by hand so 1-2mm tolerance would be fine to start with.

many thanks for all the advice i am taking it all on board

JAZZCNC
17-03-2014, 01:14 AM
i was wondering about using 60x60 or 80x80 for the z axis but the 40x80 in a relatively short length seams crazy strong as it is.

Yes it may seem strong Now but promise you when there's a spindle on the end with cutting forces acting on it then at full extension at this length which you would be while cutting ply it will twang like a guitar string.!!
The Z axis is THE single most important area on a CNC machine and seen as your going to so much trouble and expense using Profiled linear rails etc why spoil the broth for a pinch of salt.?

Regards R&P then yes it would work ok and seen as your using it on other axis makes sense but you would still need drive it from both sides, thou it would be easy enough to run a shaft across the back of profile. As would it to connect ballscrews with a timing belt, which woud be my first choice.

Tip for you if you use the Bosch Rexroth 45 x90 or it's equivlent then the BK/BF12 bearing block hole centres match the slots and make fastening very easy.
This stuff Profile 45x90S slot 10 (http://www.motedis.co.uk/shop/Slot-profiles/Profile-45-B-Type-slot-10/Profile-45x90S-B-Type-slot-10::99999415.html)

gavztheouch
17-03-2014, 01:29 AM
What is the biggest diameter collet you can get in that spindle. For roughing out you probably want some large diameter tools.

charlieuk
17-03-2014, 12:16 PM
all the aluminium i have used so far is ether 40/80 or 80/80 bosh compatible from kjn, i don't think changing the z will be to hard, i have some spare 40/80 i can use however the motor mount may have to go on the top like you have drawn which isnt so great as i have a hight restriction and need to keep it as low as posable so will have to see what i can come up with.

i dont think its going to be posable to do the y with one ball screw any were near the centre as the z will get in the way which mean needing two which would be a nice build but would cost something like a further 350 compared to about 60 ish that rack and pinion would be so will have to have a little think.

I think the max size bit would be 19mm but most i think are just 1/2" shafts so nothing crazy. foam likes to be cut quite quick other wise you get melting issues so you don't need big bits.

gavztheouch
17-03-2014, 12:20 PM
Would it be possible to use a timing belt and ballscrew. The ballscrew does the main postioning work and the belt just prevents the gantry from racking?

charlieuk
18-03-2014, 10:13 AM
i think a belt and ball screw may end up getting more complicated than r&p and i would rather try and keep it as simple as posable although i expect it would work.

Just thinking out loud...

If the z axis was mounted to one side of the y gantry and the same side as the rack and pinion and as close to the rails as posable would racking be such a issue?

At present the y rails are 360mm apart, would reducing that help and if so what sort of distance before racking would not be so much of a worry 100mm? 150mm? 200mm? im am just trying to get a good idea in my head of how much of a factor it will be.

many thanks

FatFreddie
18-03-2014, 02:22 PM
I've been wondering along similar lines - if the gantry is stiff enough in the axis it's being driven in, is it necessary to drive both ends of it? Thinking of a design where the drive end bearings are wider spaced and the gantry is triangulated...

charlieuk
18-03-2014, 10:19 PM
on the machine in the video they are running the x on 3 carriages, 2 on the top and one on the bottom with a belt drive along the top so i gess they have found a way around it, maybe that is why they only have 3 carriages ?

charlieuk
22-04-2014, 09:12 PM
managed to get the plates made through the forum so i can mount up the x and y carriages and all so some adapters to mount the ball screw blocks to the ali extrusion, its taken a while but now should be able to get the x and y properly rolling.

The next step is going to be best to mount the rack and how i am going to do the motor mounts and keep things relatively simple. I guess i will also need to decide what motors i am going to use so i can get the mounting holes ect right.

Any advice here would be great. From what i see some people are using a pivoting motor mount with a spring to keep it in tension and others are just having a ridged mount that you set the meshing and then leave alone.

I have found this in the usa but i was hoping to use mod 1 rack and it looks like that is made for mod 2.

any advice would be great and many thanks in advance for any info you guys can give

best regards charlie

ps if any one is in the sussex area and can lend any help or advice it would be very much appreciated and repaid any way i can.

charlieuk
25-04-2014, 09:30 PM
X and Y mounted up and rolling finally.

Skysurfer
26-04-2014, 01:30 PM
Jeez, that's one helluva build! :smug:

charlieuk
27-04-2014, 09:43 AM
could any one tell me if i was to run two ball screws for the y axis what is the best or most practised way of running them as a pair? im my mind i am thinking there are a few options, i have had a search but not found to much as im not to sure on the terms used for this. Is it better to run two motors one on each or put a motor on one and have a belt going across to the other or have a centrally mounted motor with a belt going to each?

Also After a few people have mentioned it i am wondering if i would be better go for a hybrid closed loop stepper system due to the length of the x? servos are defiantly way out of my budget but is closed loop worth considering? can you run it on just one out of the 3 axis then upgrade the rest later?

cheers charlie

charlieuk
27-04-2014, 11:52 AM
sorry i ment to add this which is me just playing around with the z axis ball screw and seeing how it may work on the y, it looks like it could be quite straight forward to mount it up and just use a angle bracket of the carriage to the ball nut mount.

charlieuk
27-04-2014, 07:43 PM
Call me sad but really getting excited now! Just mocked the z axis up with some wood plates to try and figure a few things out and all looks like it should be relatively simple.

I have decided to go with all your suggestions and do the double ball screw and all so add the 3rd vertical rail to the Z axis. Its going to cost a lot more but it will actually probably be more simple and figured probably give me less headaches in the long run and wont kick myself wishing i had done it that way.

The X axis will have to stay rack and pinion as i cant see any other real way to do it other than belt which people have said is not such a good idea on that length.

I will order parts tomorrow then will need to get a few more plates made up to bolt it all up.

still no real idea on what motors im going to use but hopefully some one will be able to help me with that.

charlieuk
05-05-2014, 11:04 PM
Got the two 1100mm y axis ball screws through in the post and mocked up some plates that i will need to get made, now need to add the 3rd z axis rail and figer how to fit it all in together so it nice and clean.

JAZZCNC
05-05-2014, 11:43 PM
Sorry I some how missed the post from a week ago.!! . . . . I would definately join the screws together with a single motor and belts. Far more accurate and less hassle.

You really won't regret those 2 screws and extra rail on Z axis.

Looking good and keep it going, shame your so far away I'd gladly help.

charlieuk
06-05-2014, 12:00 AM
cheers no worries i have been advised that its been better to drive the ball screws with separate motors but then wired together so id there is any interference on start up the same goes to booth so not to sure now. I liked the idea of just bolting the motors straight up to the ball screws without having all sorts of belts and pulleys but having just the one motor would make some things easier. Another job this week is figuring out the x axis drive and what ratio i need to gear the stepper to.

JAZZCNC
06-05-2014, 12:15 AM
Well who ever told you that is wrong.!! Problem comes from Mid band resonance and how the drive works out compensation and correction. When you have 2 motors connected to one drive it doesn't know which motor to apply the compensation correction to so it can throw the other motor into resonance.

I can tell you from experience that screws connected with belts are by far the best option and most accurate with least hassle other than attaching pulleys.

charlieuk
06-05-2014, 12:21 AM
ok cool i will try work that into the design. is there a standard method for doing the belts i couldn't find much when looking last week?

JAZZCNC
06-05-2014, 12:51 AM
ok cool i will try work that into the design. is there a standard method for doing the belts i couldn't find much when looking last week?

No real standard way regards laying out as it's often machine dependant but regards sizes etc then there is kind of standard in that most use in HTD 5mm pitch belts and either 15 or 25mm wide. Pulley sizes will depend on if your having a ratio but from experience between 18-20T for 1:1 ratio is best. If you go too small you risk excessive wear and jumping teeth due to fewer teeth being engaged. Equally don't go too large on pulley size as the extra inertia will have a negative affect.

Really this is something you should have worked out before ordering the ballscrews as you could have had the screws machined in such away that they suited pulleys and made life easier.

charlieuk
06-05-2014, 01:42 PM
ok many thanks for that. is it best to drive one screw direct with the motor and then take a belt of that to the other side or have the motor central and run two belts to ether side or is there another way? i could do with keeping all the motors and belts down to the one end if posable.

EddyCurrent
06-05-2014, 03:46 PM
This is useful, http://www.mycncuk.com/forums/machine-building-faqs-problems-solutions/5848-calculating-timing-belt-lengths.html#post43225

charlieuk
06-05-2014, 04:25 PM
found this on google turns out i was searching the wrong name

is this the sort of thing i need to do? I only have 265mm between the centres of the ball screws ether side so the belt wont need to be that long

JAZZCNC
06-05-2014, 04:41 PM
Ah ah think I drew that for someone on here long time ago when I used Rhino.!! . . . If not I've done something very similair for someone.

But yes that type of thing thou in your case I'd just offset the motor to one side for ease of build and neatness. Doesn't matter if it's offset with such a short belt.

charlieuk
06-05-2014, 05:02 PM
cool that should be fairly simple then as i can get a pulley straight on the shaft and motors, i may have to put a extra pice of extrusion across anyway to take the motor mount so not sure go off centre is going to make it to much neater, i think i have a little ocd on things being symmetrical as well.

What i will also do is try and get the bk and bf blocks in line with the top of the alli so the stepper does not drop to far bellow the gantry. I would have loved the belt and motor to be all inside but that doesn't look possible with this design.

Skysurfer
08-05-2014, 12:02 PM
Jazzcnc, thanks for that, I've been thinking what's best for this kind of setup, too.
Helluva build, eh?

charlieuk
08-05-2014, 12:47 PM
started to draw things up the hole y and z bit is proper complex and proving a bit of a head spinner but slowly making progress. just ordered a few bits from kjn to replace the main beam on the z with 80 x 80 and a hole load more t nuts. (You can never under estimate just how many you will need!) The aluminium while expensive is really good if you are not 100% sure on what you are doing as its so easy to go back a step or two if you forget something.

I have all so ordered a number of triangular corner plates to go on the table to give it belt and braces as there is the tinniest bit of movement if you hang from the arm.

While this is a huge machine and a bit of a different design im not sure it that much different to anything else except the x axis is very long!

im allso working on idea for the x axis rack and pinion set up/gear box. I have done a very very crude mock up, i have been told that it is probably safer to go for a fixed pinion setup rather than spring loaded as it is a lot less likely to go wrong and it is very hard to get enough pressure with out a very big spring. I am going to try and work some way of making a manual tensioner to help press the pinion up into the rack before bolting it up tight.

I Started to read the what motor threads and got to admit im wondering if i will ever figure it out myself! im not a great one for maths.

charlieuk
10-05-2014, 10:42 PM
............

Lee Roberts
10-05-2014, 11:30 PM
and figure what i am going to do with the x axis ie a fixed mount or spring loaded for the rack and pinion.

Hi Charlie,

From the diy machine builds i've seen/read, i think they all used the spring loaded method when it came to the R&P. The build is coming along nicely, good luck with the rest.

.Me

charlieuk
10-05-2014, 11:40 PM
cheers lee i will have to see if i can come up with something then as a few people have said it can be more effort than its worth as you need to have it under very high tension otherwise it can slip out the rack and then you get even bigger problems. I have been wondering if it is almost posable to get a pice of sprung steel that could work like a leaf spring that you could tension right up.

many thanks

charlieuk
10-05-2014, 11:54 PM
i also spoke with cnc4 you and zapp regarding motors and drivers cnc4you recommended for the y and z axis ball screws there nema 23 3.1 with there cw6060 driver and zapp recommended there SY60STH86-3008B motor and DM856 driver.

from my very basic knowledge it looks like the motors are the same ? can any one give me any advice on the two drivers that have been suggested on which is better?

DM856 Digital microstepping driver (http://www.zappautomation.co.uk/en/digital-stepper-drivers/738-dm856-microstepping-driver.html)

Stepper Motor Driver 6.0A 20~60VAC or 24~80V CNC Microstepping CW6060AC (http://www.cnc4you.co.uk/index.php?route=product/product&path=82&product_id=269)

many thanks

JAZZCNC
11-05-2014, 01:02 AM
There's nothing between the motors. I would definately go with the digital drives thou in My experience I'd go with EM806 rather than the DM856 as they are worth the extra. They have better resonance handling and stall detection and just seem to run motors that bit smoother than the DM856.

With the rack I'd go with sprung loaded as it keeps backlash to a minium and lowers rack wear. Problem with fixed is you need to be very precise with rack alignment and pinion tension/engagement otherwise it wears quickly and can stick or bind causing motor stalls.
Sprung loaded is more work but more forgiving and if done correctly gives better backlash and longer life.

charlieuk
11-05-2014, 01:27 AM
There's nothing between the motors. I would definately go with the digital drives thou in My experience I'd go with EM806 rather than the DM856 as they are worth the extra. They have better resonance handling and stall detection and just seem to run motors that bit smoother than the DM856.

With the rack I'd go with sprung loaded as it keeps backlash to a minium and lowers rack wear. Problem with fixed is you need to be very precise with rack alignment and pinion tension/engagement otherwise it wears quickly and can stick or bind causing motor stalls.
Sprung loaded is more work but more forgiving and if done correctly gives better backlash and longer life.

Cheers thanks for that, are the digital drivers cnc4you good alternatives to the em806 only that they have been super helpfully through my build and
offer great backup and support from them so far.

I will do a little more searching to see what I can find for the rack and pinnion and come up with some sort of design unless zany one knows of something avalable for mod 1 rack? Many thanks

JAZZCNC
11-05-2014, 09:46 AM
Cheers thanks for that, are the digital drivers cnc4you good alternatives to the em806 only that they have been super helpfully through my build and offer great backup and support from them so far.

I understand what you mean regards supplier being helpful and it goes along way in my book too but you have to remember with any supplier they are always going recommend and Big up what they sell for obvious reasons. Helpfullness does also needs to be factored in but must say from folks I help and my own experience Gary and staff at Zapp are not unfriendly or awkard.!

Regards the drives then Honest answer is I haven't used those drives so can't comment on them. What I will comment on thou is the things they don't have compared to the Leadshine EM806 or DM856 which can become a major issue in some machines, esp large steel machines and machines with slaved axis.? . . . Resonance handling and stall detect.!

Most decent drives, inc the CW6060AC will have Resonance handling features built into them and some like the CW6060 will have more advanced algorithms to deal with resonance than others but essentially they still do the same in that they use a fixed frequency range or field of view along the motors speed curve.
The Leadshine drives come with a COM port so you can connect to them via software and adjust the drives resonance parameters. This can be priceless if you have a machine that is resonant and happens to be producing resonant frequencys outside the drives compensation field of view or dipping in and out so causing irratic or rough running motors.
If this does happen on fixed range drives then your stuffed and stuck with it but with EM806 drives you have full and fine control of the resonance handling.
If your thinking does this happen.? Then yes it does, esp on large steel framed machines or machines running resonant drive systems like R&P. It's just that often people don't know they have resonance problems as the drive is doing some compensation whick masks it and they just accept that the speeds or way machine runs is just how it is.!! This is Because unless resonance is really bad it doesn't stop motors running it just makes them run rough or lowers the speed you can get from them before stalling.!
Does it happen Often then again some times yes, esp on cheap drives but people don't know it. In most cases then folks won't have a problem but if you do have a resonance issue then you'll be highly pleased you bought the EM806.!!

This takes us nicely into the Stalling motors.? The EM806 as a nice feature in that it detects motor stalls and provides a Fault signal which can be used to E-stop the machine. This for machines running slaved motors is Vital to me and after using these drives I wouldn't run any slaved axis machine without this feature.

There are other nice features the EM806 offers like full Current tuning control and fully adjustable Micro stepping and fine adjustment amp setting 0.1A but they are secondery to the other 2 features which IME are worth that little extra.!!
Between these features if you have any issues you can deal with them and tune them out rather than just having to Live with them.!! . . . Priceless.!!

GEOFFREY
11-05-2014, 10:41 AM
I will do a little more searching to see what I can find for the rack and pinnion and come up with some sort of design unless zany one knows of something avalable for mod 1 rack? Many thanks[/QUOTE]

Hi, first of all let me say that I am a machine user(converter) and have never built a machine. I think that your giant will be awesome for the uses you plan. With regards to tensioning the R&P, I think the most simple way would be to pivot the drive and have an extended arm with an adjustable slide weight to let gravity do the tensioning. Perhaps this is just too easy, I'm sure I will soon hear why its a stupid idea, but I do love simplicity!!! G.

charlieuk
11-05-2014, 09:04 PM
i was wondering about that but i from what i have been told it need to be under pretty high tension which would require a lot of weight or a very long arm to hang it from i guess.

charlieuk
12-05-2014, 12:07 AM
Many thanks for that jazz although i am only just strating to learn about this side of it it does make sense what you are saying.

cnc4you have been super helpful and even dropped in to see them and they spent ages going through everything and offered full support on getting it all wired up correctly and running and even offered to switch parts over if for some reason i needed to so seeing as this is my first build that was quite reassuring. Im not saying zapp dont offer the same but i just have only spoke very briefly to them but they we very quick at giving me advice on the motors.

this was the digital driver i think cnc4u have added recently, i have no idea if it is suitable or similar to the EM806 you recommend
Digital DSP Stepper Driver 7.2A, 80VDC or 60VAC CWD872 (http://www.cnc4you.co.uk/index.php?route=product/product&path=82&product_id=305)

when you mention slaved motors are you talking about two motors on one axis or one motor driving the two screw like i am having?

im happy to get the product from were ever but feel it would be nice to support kevin and brian if they have a suitable product as i could do with as much help as posable when it come to getting the motors and electronics up and running.

JAZZCNC
12-05-2014, 01:21 AM
this was the digital driver i think cnc4u have added recently, i have no idea if it is suitable or similar to the EM806 you recommend
Digital DSP Stepper Driver 7.2A, 80VDC or 60VAC CWD872 (http://www.cnc4you.co.uk/index.php?route=product/product&path=82&product_id=305)

They are similair to the EM806 in that they use PID technology and can tune them selfs to the motors but they still lack the abilty to go in and tweak thru software in the avent of resonance problems. Now in practice it's likely won't have any troubles but if you do then you still can't do anything about it other than alter the Micro stepping which is less than ideal.
To be honest IMO Leadshine lead the way when it comes to this technology and the others are either cheap copy's or better quality copies playing catch up. My gut feeling is these drives are ok Copies of leadshine technology but can't use the Software option for legal reasons.

Don't get me wrong I'm not saying these drives are no good because I've not used them before but they don't give the same flexabilty or features as leadshine drives. That said, it could be said, they don't cost the same either so your not paying for the features either and if you don't need them why pay for them.? . . . Which is fine if you can be sure your not going to run into resonace problems but like I pointed out before if you do you'll wish you'd payed 15-20 more to be able to tune it out.!

Being in business I applaued your attitude regards supporting helpful business or people and Having help and advise on hand is also valuable but hey you have a Forum full of help and I've offered my number so you have experienced phone support if you need it so I wouldn't compromise my machine just to carry favor.! . . You can still support them by buying other items from them, like there motors which are Ok.



when you mention slaved motors are you talking about two motors on one axis or one motor driving the two screw like i am having?


I mean 2 motors working same Axis that need to run in sync. Imagine the carnage that happens when one motor stalls but other keeps going when 2 motors slaved to the same axis.!! . . . You need some way to tell the other motor to stop as well. The stall detect and it's fault signal provide this abilty.
While the stall detect is mostly of benefit to slaved motors it is also useful to stop the machine when using single motors on each axis in case one axis stalls. This can often save the job if a stall does happen and your not around or quick enough to E-stop the machine before too much damage is done.
(Often Stalls happen at higher feeds, like rapid speeds, when torque is at it's lowest. So you can recover from stall before damage is done because rapid move stalls tend to just mean positional loss and are not engaged in the cut or material.!)

charlieuk
12-05-2014, 09:15 AM
Many thanks for that info again, i will most likely then go for the EM806 drivers from zapp as it does sound like a worth will benefit as the machine is so big in the x axis.

cnc4you nema 23 were as zap call them SY60STH86-3008B, will they in fact be exactly the same? i will most probably get those and the rest of the little parts from cnc4you.

Zapp mentioned that it may be worth running a nema 34 on the x axis with possibly one of there 3 to 1 gearboxes which would allow a direct drive which may simplify things but not sure if i will be able to fit it all in like that without having to mount the motor up top and still have the belt that i was originally planning.

Does any one have any experience with the quality of the zapp gearboxes for the nema 34?

Many thanks again for all the help sorry for so many questions but i just want to be double sure on every thing as it is all totally new to me and obviously a lot of money involved in it all that is extremely tight.

gavztheouch
12-05-2014, 10:05 AM
Looking forward to seeing this beast up and running.

charlieuk
12-05-2014, 10:19 AM
Your not the only one! so long as i don't go broke before i get it done hopefully it wont be too too long. Almost got all the plates drawn up on cad for the y and z but now looking for two suitable pulleys to use for the y axis that go ether side of the motor like in the pic i posted on the last page

tried ebay but cant think of what search to do to narrow it down? any ideas it just needs to have a flat surface and barring for it to run on.

IanParkin
12-05-2014, 10:47 AM
Charlie
Just use as many bearings as you need to cover your belt width
mount them on a bolt and place shim washers between each bearing( on the id)
if you use a bearing say 30mm od 10 mm id and width say 9mm thats a 6200 very cheap and easy way of making idler pulleys

Ian

Jonathan
12-05-2014, 11:26 AM
It's hard to say how good the driver from CNC4You is, as the description doesn't state what algorithm they use - just some 'buzzwords' which appeal to those who don't know so much about the subject. We can therefore only speculate as to which is best - e.g. the lack of software tuning could be a disadvantage, or it could just mean the drives uses algorithms to automatically 'adapt and learn', so manual tuning is not required.


cnc4you nema 23 were as zap call them SY60STH86-3008B, will they in fact be exactly the same? i will most probably get those and the rest of the little parts from cnc4you.

I have not observed a tangible different between the two motors from the measurements I have taken.


Zapp mentioned that it may be worth running a nema 34 on the x axis with possibly one of there 3 to 1 gearboxes which would allow a direct drive which

You appear to have ballscrew on the Z-axis, so the mechanical advantage to the motor to lift the axis is already huge. You definitely don't need and therefore shouldn't use a bigger motor on the Z-axis as it is important for this machine to have quite high feedrates, which you certainly wont get with a Nema 34 motor, especially with a gearbox.

charlieuk
12-05-2014, 12:18 PM
Arrr yes i totally forgot about that im sure now i have seen pictures of that just totally forgot i will defiantly do that many thanks.

charlieuk
12-05-2014, 12:26 PM
It's hard to say how good the driver from CNC4You is, as the description doesn't state what algorithm they use - just some 'buzzwords' which appeal to those who don't know so much about the subject. We can therefore only speculate as to which is best - e.g. the lack of software tuning could be a disadvantage, or it could just mean the drives uses algorithms to automatically 'adapt and learn', so manual tuning is not required.





I have not observed a tangible different between the two motors from the measurements I have taken.



You appear to have ballscrew on the Z-axis, so the mechanical advantage to the motor to lift the axis is already huge. You definitely don't need and therefore shouldn't use a bigger motor on the Z-axis as it is important for this machine to have quite high feedrates, which you certainly wont get with a Nema 34 motor, especially with a gearbox.


Many thanks Jonathan for that i will see if i can find out more about the cnc4you drivers if posable but it sounds like all you lot use the others so hopefully all your support will be sufficient to get me out of any problems im bound to have.

the z axis and y axis is a ball screw and will be the nema 23 3nm . The long X axis is what they suggested the nema 34 possibly with a gearbox for as the gantry weight will be some where around the 60kg area sorry i may have confused you.

best regards

Jonathan
12-05-2014, 12:39 PM
the z axis and y axis is a ball screw and will be the nema 23 3nm . The long X axis is what they suggested the nema 34 possibly with a gearbox for as the gantry weight will be some where around the 60kg area sorry i may have confused you.

Sorry, that was my fault - for some reason I read 'x axis' as 'z axis'. The gearbox is a reasonable suggestion for X - you need something there (be it a gearbox or belt) to get sufficient resolution and better acceleration.

charlieuk
12-05-2014, 12:46 PM
no worries yes im going to see if i can fit the gearbox in as it will be one less thing i will have to have made assuming they are good quality.

charlieuk
12-05-2014, 04:47 PM
sorry more questions

i am trying to find out what motor size i need for the x axis and to do so i obviously need to figure out what speeds i want to obtain from the machine.

From the research i have done i am aware that there is obviously a optimum speed for each material.

surfboard machines looks like they are cutting at around 10-12 inches per min or around 15,000 mm min which is obviously very fast i assume because foam is soft and the cutting path is very long.

for plywood which will be most probably the hardest thing i will be cutting it looks to be a third of that at around 5000 mm per min.

will this huge range be a problem?

i asume to get the high feed rate it will require a larger motor with more gearing?

from what i understand you have the cutting speed and the rapid speed which is what i under stand as the max speed it can travel when not cutting. is the rapid speed something you just find out when you get it up and running and see how fast it goes under no cutting load? or is it something that would effect choice on motors and gearing?

while i am not going to be in a mega rush to get things cut i dont waiting hours and hours and hours for it to cut a big surf board if posable.

best regards

JAZZCNC
12-05-2014, 05:32 PM
Many thanks for that info again, i will most likely then go for the EM806 drivers from zapp as it does sound like a worth will benefit as the machine is so big in the x axis.

cnc4you nema 23 were as zap call them SY60STH86-3008B, will they in fact be exactly the same? i will most probably get those and the rest of the little parts from cnc4you.

Good idea and I've not seen any differance between the motors either so your good to go there.!


Zapp mentioned that it may be worth running a nema 34 on the x axis with possibly one of there 3 to 1 gearboxes which would allow a direct drive which may simplify things but not sure if i will be able to fit it all in like that without having to mount the motor up top and still have the belt that i was originally planning.

Does any one have any experience with the quality of the zapp gearboxes for the nema 34?

Yes thats what I've done in the past and they are nice units Italian made I believe.? Just be aware thou the Nema34 motors don't spin as fast Nema 23 motors unless running High voltage drives(240V ac) so if your needing certain feeds rates for cutting your foam etc then be sure to select the correct ratio but other than that it's a good solution. Also be aware that the gearbox does make the overall motor/geabox length quite long so check you have room.


Many thanks again for all the help sorry for so many questions but i just want to be double sure on every thing as it is all totally new to me and obviously a lot of money involved in it all that is extremely tight.

Yes but it will be worth the trouble, don't look at the extra expense as costing more think of it in terms of saving money.? You'll only be spending one time not replacing and regreting.! . . . . To quote My Guru Ger21 . . "The cheapest way to get a good machine is to spend more money."

charlieuk
13-05-2014, 10:26 AM
ok so for the long x axis to get the fast speeds zapp have recommended the nema 34 8nm motor SY85STH118-6004B Nema 34 High Torque hybrid stepper motor (http://www.zappautomation.co.uk/en/nema-34-stepper-motors/383-sy85sth118-6004b.html)

but said that the EM806 drivers would not be powerful enough so it would have to be the 2m2280n driver which looses the functions we have been discussing unfortunately. 2M2280N Digital microstepping driver (http://www.zappautomation.co.uk/en/digital-stepper-drivers/318-2m2280n.html)

from a users point of view is it worth reducing the speed requirement just to run the other drivers?

while i want to build the machine to a good quality i just need to be careful the costs down spiral out of control.

JAZZCNC
13-05-2014, 05:52 PM
ok so for the long x axis to get the fast speeds zapp have recommended the nema 34 8nm motor SY85STH118-6004B Nema 34 High Torque hybrid stepper motor (http://www.zappautomation.co.uk/en/nema-34-stepper-motors/383-sy85sth118-6004b.html)

but said that the EM806 drivers would not be powerful enough so it would have to be the 2m2280n driver which looses the functions we have been discussing unfortunately. 2M2280N Digital microstepping driver (http://www.zappautomation.co.uk/en/digital-stepper-drivers/318-2m2280n.html)

from a users point of view is it worth reducing the speed requirement just to run the other drivers?

while i want to build the machine to a good quality i just need to be careful the costs down spiral out of control.

If your going to run Nema34 motors then these are the drives you want. Kinco are good drives and while you won't have the abilty to tune out resonance they are still very good drives with advanced alogrithms for dealing with resonance and motor tuning so the chance of resonance being a problem is very very low. Also they provide a Fault output so you can use this to E-stop the system if you have stall just like the EM806.
I wouldn't lower the spec to save money and these drives are 100% what you need with 8nm Nema34 if you want resonable speed from the motors. Also being 240Vac you won't need a power supply with these drives so you have to factor this into the mix. Obviously if your not using on all axis you'll need a PSU for the other axis.

Don't be tempted to try running smaller Nema23 motors with gearbox and heavy gantry running at high feeds because while the smaller motors may provide the speed and enough torque to move the gantry they will struggle to provide the torque needed to handle the slowing down and inertia of the gantry from higher feeds. The affect would be positional loss from steps being lost due to pushing affect.

Understand your point about keeping handle on the costs but The truth is that you can have high feeds but they do come at a cost. While 3.2 or 4Nm Nema23 motors run at 75V on the EM806 connected to correct gearboxs would work fine you would have to accept the fact they would be limited to what feeds/acceleration they can provide and the balance between working within an acceeptable motor tuning range and one that will cause miss steps etc will be a lot finer.
The High power Kinco drives and Nema 34 motors are the correct choice to deal with all the friction and inertia your going to encounter using R&P with gearboxs and heavy gantry and in the long run they will save you money by not needing replacing if you found the smaller setup just couldn't cut the mustard.

Unfortunatly if you want the best possible machine your just going to have to lube up Bite down hard and take it like a Man.!! .:dejection:

charlieuk
13-05-2014, 10:25 PM
Cool that makes scene so will go with

nema 23 3nm for the y and z axis with the Em806 driver and the 8nm nema 34 with the 2M2280N driver

love the idea that the 2M2280N dont need a separate power supply as its going to be one less thing for me to worry about.

i dont suppose theres a driver that does the same for the other motors even if they were a little more, just thinking it would be one less wiring and things for me to learn wire and understand?

Just trying to sort out how i am going to do the x axis drive, i need to get about a 6 to 1 ratio. i was looking at the cnc router parts gearboxPRO Rack and Pinion Drive, Nema 34 | CNCRouterParts (http://www.cncrouterparts.com/pro-rack-and-pinion-drive-nema-34-p-226.html) but they don't do it for mod1 rack is there anything similar available else were? Unfortunately i don't have any form of mill at the moment to make any parts so i am having to get most parts of the shelf.

JAZZCNC
13-05-2014, 10:55 PM
love the idea that the 2M2280N dont need a separate power supply as its going to be one less thing for me to worry about.

i dont suppose theres a driver that does the same for the other motors even if they were a little more, just thinking it would be one less wiring and things for me to learn wire and understand?

Don't know of any that use 240Vac but I believe you can get versions of the Am882 and EM806 that will allow you to use AC voltage rather than DC so you can just use the correct size transformer without having to rectifie to DC and use smoothing Capacitors. That said building a DC toroidal power supply isn't difficult or rocket science.

charlieuk
14-05-2014, 10:31 AM
just to give you more of a idea on what i am planing to use the machine for

here is a hand shaped board hopefully the machine will do this hole process for me and give me much higher accuracy and control over the shapes

JAZZCNC
14-05-2014, 11:40 AM
just to give you more of a idea on what i am planing to use the machine for

here is a hand shaped board hopefully the machine will do this hole process for me and give me much higher accuracy and control over the shapes

12405

I have a helped someone in the past who lives near me with noise issues who shapes foam moulds for custom car body panels with a much simpler setup that what you have planned. See is video below of what he makes and the machine it's done on. (Which by the way I've had nothing to do with making the rough arse thing. . .lol)


https://www.youtube.com/watch?v=cv-FrT0fA-c


https://www.youtube.com/watch?v=Vw1KXIgT96s

charlieuk
14-05-2014, 12:01 PM
Thanks for those vids i had not seen them before if i can get that sort or accuracy on foam i will be more than happy i gess it comes down to the wood were the extra money spent will be noticed. I am hopping one day to make some moulds for boards and other things as well if it does turn out to be fairly accurate.

charlieuk
20-05-2014, 05:43 PM
I have decided to use a planetary gearbox for the x axis which will be direct drive on to the rack and also to use a spring tensioned mount for this. However i cant seam to find anything suitable alredy available unfortunately.

i have done a very crude mock up to get the ruff idea and to cheque for space ect.

Can any one give me any suggestions on how would be best to do the pivot on it, im thinking maybe i need some sort of sealed barring in there to keep it moving smoothly all be it hopefully only fractions of a mm.

Allso any other suggestions to the design that may be needed as i am pretty much just making up what i think will work from my head.

( sorry i cant figure why the pictures seam to rotate them selfs around)

charlieuk
21-05-2014, 01:53 PM
I am just about to have the big wooden plates holding the z axis in the picture machined up in aluminium but wondering what thickness to go any suggestions? all the other parts i am having done will mainly be in 10mm but wondering maybe i should go higher for these to maybe 12 or 14 even

charlieuk
12-06-2014, 12:18 AM
things are starting to move again i have just started to get some of the electrics together and things like the spindle is on order. I am all so in the process of designing a sprung motor mount for the rack and pinion and will be looking for some one to be able to machine it if there are any willing people?

charlieuk
23-06-2014, 03:45 PM
i just got my 2.2kw spindle and mount through in the post and now have the task of fixing it to my 80x80 ali extrusion and was just wondering hows best to do it? The mounting flanges are a lot wider than the extrusion so im wondering if its best to tap the back of the mount and drill some holes all the way through the extrusion so i can bolt it from the back?

JAZZCNC
23-06-2014, 04:39 PM
I would go with a Piece of plate same width as spindle mount fastened to extrusion with some nice strong bolts then fasten mount to that. This will make setup and tramming the spindle easier and backup the mount a Little.!

charlieuk
23-06-2014, 11:06 PM
i did a little mock up in wood. In a aid to try and neaten things up i have taped some holes on the back of the mount and bolted it to the plate the heads of these bolts then actually locate into the slots of the aluminium profile then there are four bolts which actually bolt it to the aluminium extrusion using slide nuts. At the moment they are just m6 but i will change those to m8 when i get some larger slide nuts or tap some out.


Ps im not sure why all my portrait pictures get rotated to landscape?

charlieuk
29-07-2014, 11:36 PM
Progress with the electronics! I now have working steppers motors and functioning home and limit switches, to many this is probably not much of a big deal but it was the most daunting part for me and with a lot of help from two very kind people who im sure know who they are i have managed to get the basics going.


https://www.facebook.com/photo.php?v=10154435267165297&amp;set=vb.522155296&amp;typ e=2&amp;theater

charlieuk
30-07-2014, 11:48 PM
more progress today with figuring out how to fit the home and limit switched and and all so the drag chain to the x and y axis. More parts arriving tomorrow so hopefully i can make more progress.

I still have to sort out the rack and pinion drive system and i have to be honest i have been wondering about belt drive again.
any advice on improvements is more than welcome.

charlieuk
05-08-2014, 09:24 PM
vfd mounted and the aluminium plates to mount the y and z axis carriages and steepers , its been a bit of a jigsaw trying to fit it all but getting there.all so run some trunking and a few other bits and bobs.

still waiting on a gearbox to do the x axis and now just got to order some belts and pulleys to get the drives connected.

charlieuk
07-08-2014, 04:10 PM
what are the best methods for tensioning timing belts on to steppers. I have slots for adjustment but need some sort of screw type adjuster to get the belt relatively tight. Cant seam to find much on here.

EddyCurrent
07-08-2014, 09:38 PM
what are the best methods for tensioning timing belts on to steppers. I have slots for adjustment but need some sort of screw type adjuster to get the belt relatively tight. Cant seam to find much on here.

Section 10 page 45.
http://file.lasersaur.com/docs-thirdparty/The_World_of_Timing_Belts.pdf

I just used the same technique as putting an alternator belt on, stick a large screwdriver in behind the motor and lever it out until the belt is at the 'correct' tension, now tighten the bolts.

charlieuk
08-08-2014, 10:39 AM
i guess that keeps things simple! the pulleys i have have two grub screws for securing however the shaft is totaly round, whats best to do there? put a flat for them or drill a hole or something? cheers charlie

EddyCurrent
08-08-2014, 10:52 AM
i guess that keeps things simple! the pulleys i have have two grub screws for securing however the shaft is totaly round, whats best to do there? put a flat for them or drill a hole or something? cheers charlie

Use two grub srews M4 will do, these MUST be 90 degrees apart around the pulley boss (i.e. NOT opposite each other). File a small flat on the motor shaft for one of these screws only. Where the flat is, use a flat bottom grub screw, for the other screw grind it to a point so it digs into the shaft once tightened.

charlieuk
08-08-2014, 10:55 AM
cheers many thanks thats great will get on to that

Clive S
08-08-2014, 10:56 AM
The way I have done mine is to put a copper plug (pad) into the grub screw hole. I have done this by using a bit of solid core earth wire from twin&earth cable just lightly swash it with a hammer and then cut a piece off that will fit down the hole so that the flat bit is on the shaft then just tighten the grub screws. That way you don't mark the shaft.
I have found that it is not necessary to put a flat on the motor shaft. ..Clive

EddyCurrent
08-08-2014, 11:52 AM
The way I have done mine is to put a copper plug (pad) into the grub screw hole.

Im sure the locknuts for my ball screw BK blocks had a grub screw arrangement like that.

Clive S
08-08-2014, 12:23 PM
Im sure the locknuts for my ball screw BK blocks had a grub screw arrangement like that.
Yes all mine did as well it's a common way of fixing as it does not damaged the shafts so that makes them easy to remove later if necessary. ..Clive

charlieuk
12-08-2014, 08:36 PM
belts arrived, i had to go with 5 teeth less on the motors to get it to fit unfortunately well unless the belts stretch a fraction as it is right between sizes.

charlieuk
13-08-2014, 11:44 AM
I mentioned it in a post earlier that i am geting a small amount of flex from the main back uprights which for the surfboards really isn't a problem as the load on the machine will be close to nothing cutting foam however i would like to try and reduce it as much as posable. I have been wondering about two options the first being bolting a pice of 90deg angle steel to each leg ( i cant get large enough channel or T section) and the second idea was to fill each of the current aluminium legs with a resin/granite mix or maybe even a concrete mix which i have been reading about which may help in other ways as well.

Can any one give any suggestions as to what may be best?

many thanks

charlieuk
13-08-2014, 09:54 PM
any one got any ideas to the above?

Clive S
13-08-2014, 10:14 PM
Just a thought could you not bracket them to the wall? ..Clive

charlieuk
13-08-2014, 10:25 PM
I was planing on bolting it to the floor i would prefer not to rely on the wall as it may well end up being moved else were were that may not be a option.

many thanks

Clive S
13-08-2014, 10:37 PM
I was planing on bolting it to the floor i would prefer not to rely on the wall as it may well end up being moved else were were that may not be a option.

many thanks Bolting to the wall with brackets would be a quick simple fix. But if you have to move it so that it is free standing you might be able to triangulate the back of the uprights bit like an apex roof truss on end. ..Clive

routercnc
14-08-2014, 12:23 AM
Looking at other designs on youtube I found this one. Different layout approach which would be stiffer than your cantilever. Bit late I know, but any ideas from here?
http://www.youtube.com/watch?v=9zYrr4jNfWI

In terms of improving what you have - I don't think you'll get very far filling the back supports, or adding angle iron. You are looking for a big step change to make a difference. As Clive suggested either bolting to the wall or adding diagonals on each end coming forward to the front of the machine and onto the floor would be much better.

Can you post a picture of the whole thing now it is generally together? You might get a few more ideas . .

charlieuk
14-08-2014, 08:30 AM
unfortunately due to the size of mine it cut down the options on design options as making a beam 20' long un supported would have been all most imposable.

I have all so seen videos of that design shaking violently when the router changed directions when cutting, im pretty sure mine is far stiffer that that design all ready. i Had wondered about bracing the ends but thought that possibly making the ends stiffer than the centre would be a bad thing maybe?

I will get a few more pics this morning showing the whole thing.

best regards charlie

JAZZCNC
14-08-2014, 08:58 AM
Charlie I think mentioned before that you needed diagonal bracing on the lower frame and this would help your problem quite a bit but really your easiest option is the wall.
Personally I would brace the base along its length like the black line show and try it, but at same time a few brackets to wall would cure it easy. Then if you ever need it free standing then make some triangle supports (red lines) for it which go at the rear and bolt to floor.

Also becareful with those timing belts that you don't over tighten and pull the ends of the ballscrews inwards and cause them to bend or bind. The belts don't need to be drum tight just not loose.
13085

charlieuk
14-08-2014, 02:41 PM
i have posted a few more pictures bellow you can see i have all ready braced the corners of the table area which improved it a lot and stopped any movement in that area. I could brace it more underneath but i think the flex is coming between the top of the table and the top of the verticals. would filling the extrusion help with dampening any of the vibrations or flex down? would it be a good thing to do any ways?
I will have to maybe look into bolting it to the wall but i would like to see if there was any way i could improve it before hand using other methods.

I could probably put plates in the corners of the verticals above the table as well but they would have to be taller than wide so they do not interfere with things on the table.

I have adjusted the belts a bit and just pulled them hand tight before any signs of flex from the screw so will leave it like that at the moment many thanks for that info i was originally assuming they had to be pretty tight to work.

While we are here were is the best place to source the cable and steppers from as i am going to be needing a fare few meters in total.

best regards charlie

Clive S
14-08-2014, 08:21 PM
What's the thinking behind putting the VFD on the gantry as you can't change the speed etc. when cutting. ..Clive

Jonathan
14-08-2014, 09:45 PM
What's the thinking behind putting the VFD on the gantry as you can't change the peed etc. when cutting. ..Clive

He could be using the serial interface to set the speed, but either way it will be subjected to significant vibration from the machine, which is asking for trouble.

charlieuk
14-08-2014, 10:47 PM
I have been advised that having a long lead to the spindle is a bad idea because of interference generated the vfd its is mounted floating on foam to dampen any vibrations, the speed will be controlled through mach3

EddyCurrent
14-08-2014, 11:49 PM
It's true that problems arise with long motor cables but the manual for my 2.2kW vfd says it's okay up to 50m long before you need to add output chokes. Also it recommends that for minimum radio interference the motor cable screen should be connected to ground at both ends.

charlieuk
14-08-2014, 11:57 PM
It's true that problems arise with long motor cables but the manual for my 2.2kW vfd says it's okay up to 50m long before you need to add chokes. Also it recommends that for minimum radio interference the motor cable screen should be connected to ground at both ends.

cool well i will see what its like when its up and running and decide from there, if there is a lot of vibrations still than i can easily move it, i think i could get it down to about 10-12 meters minimum but thats about it.

is there any suppliers for the cable you guys can recommend? is the stuff on ebay ok or should i go else were?
many thanks

Clive S
15-08-2014, 08:58 AM
cool well i will see what its like when its up and running and decide from there, if there is a lot of vibrations still than i can easily move it, i think i could get it down to about 10-12 meters minimum but thats about it.

is there any suppliers for the cable you guys can recommend? is the stuff on ebay ok or should i go else were?
many thanks How about this:- http://quickbit.co.uk/cable/CY-cable/CY-cable-4-core/CY-Cable-1mm-4-core
I would earth the screen at both ends. Just search for CY cable. ..Clive

charlieuk
15-08-2014, 09:06 AM
Cheers does the quality of cable vary much is there anything to look out for? the link you posted looks good. many thanks

JAZZCNC
15-08-2014, 11:03 AM
Don't like Quick bit cable it is poor quality and it's brittle, prefer CSE cables and there's hardly any difference in price. http://www.csecables.com/acatalog/Flexible-Control-Cable.html

charlieuk
16-08-2014, 01:30 PM
many thanks thats handy to know i don't mind paying a little extra when its worth it. I am still having trouble deciding how to do this x axis and wether i did the right thing going for rack and pinion as i think it is proving a little tricky to fit it all in with the gear box and tensioning system. something keeps telling me i should maybe look back into belt drive as it gives more flexibility on were you can put stuff. If it was bet drive i could easily mount the motor above the x axis like in the picture or have it stationary on one end of the main frame.

charlieuk
27-08-2014, 10:42 PM
i think we are really getting there now! i have picked up a cnc router parts pro rack and pinion drive for the x axis rather than using a gearbox at the moment, unfortunately it means swapping the rack to mod 1.5 so will have to sell the mod 1 stuff i originally got but it means i will be up and running sooner.

The cable has just arrived so thats all going in now however i just need to deside how and were it is best to situate the control box and the pc.

Is it best to keep the control box relatively close to the machine? whats the best way to protect it in a dusty environment? i was wondering about putting the box into maybe a kitchen unit type thing so it is double protected from dust and then have the computer some were less dusty but would be further away but being my first build im not really to sure what the standard thing would be on a large machine like this. Any suggestions would be great.

charlieuk
08-10-2014, 11:03 PM
Well after a lot of fine tuning it's all levelled up and the main part of the build complete just the final wiring to be done this weekend and we should have some movement. I ended up adding some extra plates to aid setting it up and stiffening and also bolted it to the wall which made a huge difference

one thing I am still looking for are the caps to fill the bolt holes on the rails if anyone knows we're to get them or what I could use.

Many thanks

charlieuk
08-10-2014, 11:37 PM
I have also got a full length switch to use as the e stop so you can grab it were ever you are along the length.

gavztheouch
09-10-2014, 01:29 PM
Very neat, looks great.

charlieuk
09-10-2014, 03:02 PM
I'm looking for some advise on we're to put all the electrics. My work space is generally quite dusty so I obviously need to protect against that. I also have the issue that all the cables will be fairly long by the time they make it any where. It's aprox 5meters from the centre of the machine and start of cable Chain to the spindle or about 8 if you take the cables to one end of the table. I have a metal cupboard I have been wondering about utilising to house some of the stuff to protect from dust but just not to sure how far I need to go with it, do I need a clean air source from out side? I was thinking of having the actual computer in a separate room to avoid dust but not sure if this would be practical? If any one can give any suggestions that would be great as I'm sure there is more to it than first meets the eye and as it's my first machine I'm not sure how closely things need to be together. Many thanks

gavztheouch
09-10-2014, 03:14 PM
You prob want a cabinet similersomething like this.

http://www.rittal.com/uk-en/product/list/variations.action?categoryPath=/PG0001/PG0002SCHRANK1/PG0021SCHRANK1/PRO0023SCHRANK1&productID=PRO0023

Most proffesional cnc machines will have a fan to cool with a filter to stop the majourity of crap getting inside. I guess you might have some long running times so you might want to add some sort of fan on your stepper drivers or at least bolt them to a heatsink or something. If you really want to push the boat out you could bolt them to a hunk of aluminium and water cool the block. My thermwood machine has a airconditioning unit attached to cool the insides of the cabinet.

charlieuk
09-10-2014, 08:01 PM
any suggestions to what sort of filters to use, i guess it will need to be fairly large to prevent the chances of it geting blocked up to quickly? how about the vfd? originally i had it mounted to the gantry but then realised it was probably better some were else. Is it something i need access to the hole time so needs to be some were accessible and if so then how would i protect that from dust all so? put it in a separate box?

cheers

JAZZCNC
09-10-2014, 10:13 PM
Big Steel box with 2 fans pulling air in thru good paper filters and one pulling it out. Filters like this. http://www.apc.com/products/family/?id=414

Car air filters also make good filters but you'll need to make an housing similair to whats in the picture. Which is easy made from thin ali sheet if you have a working machine and a good little test.

charlieuk
09-10-2014, 10:45 PM
cheers thanks i will see what i can find at a local car spares shop, should i put the vfd in with it all or separate do you think?

JAZZCNC
09-10-2014, 10:54 PM
cheers thanks i will see what i can find at a local car spares shop, should i put the vfd in with it all or separate do you think?

Put it inside with it. If you need or want to see the display then depending on VFD make you can often remove the front display and put externally.

If your controling thru software then you don't really need access but it's nice to be able to see the display and have it set for Amps. This will give an indication to cutter wear and spindle load. (thou don't think your foam will challenge the spindle any.!!)

charlieuk
09-10-2014, 11:03 PM
cool many thanks will work on that principle.

EddyCurrent
09-10-2014, 11:50 PM
like this;
http://www.mycncuk.com/threads/6565-Ready-Steady-Eddy?p=56651#post56651

make sure the fans blow into the panel (via the filter), not suck out of it, this is to keep the air pressure inside the panel higher than outside.

charlieuk
10-10-2014, 06:59 PM
Box purchased and went super size just incase I needed more room.

Clive S
10-10-2014, 10:48 PM
Box purchased and went super size just incase I needed more room.Can you not vent it from the outside with say 4" soil pipe. ..Clive

charlieuk
11-10-2014, 11:51 AM
Can you not vent it from the outside with say 4" soil pipe. ..Clive
I can do but would prefur not I would be a little conserned about moisture ect. I have got a car air filter that I will try and sort something for and the box has plenty of free air so I'm hoping it will stay fairly cool anyway. I guess adding a secondary thermometer would be a good idea.

charlieuk
12-10-2014, 07:52 PM
we tock a big leap forward today, we had the first signs of movement from all the axis!

just click the link



https://www.facebook.com/video.php?v=10154730926735297&amp;set=vb.522155296&amp;typ e=2&amp;theater

Clive S
12-10-2014, 09:05 PM
we tock a big leap forward today, we had the first signs of movement from all the axis!

just click the link



https://www.facebook.com/video.php?v=10154730926735297&amp;set=vb.522155296&amp;typ e=2&amp;theater

The first move is always the best, well done its getting there. ..Clive

JAZZCNC
12-10-2014, 09:35 PM
Excellent Charlie, Pleased could help and Nice to finally see it come alive, It's great feeling isn't it. .:applouse:

Regards the Noisey stepper then if it's one that's connected to the EM806 drives then chances are you just need to tweak the tuning in software. Could just be slightly off and now they are on the machine the resonance is different so auto config set the PID tuning to match being off the machine so re-tune thru the software and it will be fine i'm sure. . . . .. (Anyone wondering what I'm on about I'm replying here to an email Charlie sent me.!)

charlieuk
12-10-2014, 11:48 PM
Excellent Charlie, Pleased could help and Nice to finally see it come alive, It's great feeling isn't it. .:applouse:

Regards the Noisey stepper then if it's one that's connected to the EM806 drives then chances are you just need to tweak the tuning in software. Could just be slightly off and now they are on the machine the resonance is different so auto config set the PID tuning to match being off the machine so re-tune thru the software and it will be fine i'm sure. . . . .. (Anyone wondering what I'm on about I'm replying here to an email Charlie sent me.!)

yes im over the moon its turned from a pile of expensive bits into almost a working machine!

yes it is one of the ones on the 806 drivers. we did swap the cables over between the two 806's and the buzz swapped motors as well. i have the lead now so we will try will take a look at retuning tomorrow.

Many thanks again for all your help.

Charlie

charlieuk
13-10-2014, 03:50 PM
I want to extend my vfd screen to the front of the box but need a ribbon cable with fc-10p connector I just wondered if anyone had any spare as it seams I can only order a min of 10 male and female each so quite a lot for when I only need the one of each many thanks

Clive S
13-10-2014, 04:30 PM
Is this the one http://www.amazon.co.uk/30cm-FC-10P-Connector-Download-Cable/dp/B00GLQV5DS or http://www.rapidonline.com/cables-connectors/idc-cable-mounting-sockets-2-54-mm-pitch-521064 ..Clive

charlieuk
13-10-2014, 05:03 PM
Think that's the one many thanks for that! i don't think I had quite the right wording in my searches , I have order some so will soon see many thanks

charlieuk
14-10-2014, 02:58 PM
I have watched as many tutorials on Mach 3 as I can and I think I understand the basics now so have started to try and learn how to set things up however I have a few questions.

the first is what is the best way to change the direction of a stepper ie my x axis goes positive to the left and I want it to go to the right and the same for my y

the second question is with limit over rides . At the moment with that the override limit box clicks but the box doesn't go green , the auto limit override box clicks and goes green but does not seam to have any effect and I can't get it off the switch to re set without doing it manually.

Third is is that I have had a go at calibrating the x axis which is running the 1-4 gear box and the steps per calibrated at 16.2 which from what I gathered is very low so just questioning that?

Best regards charlie

JAZZCNC
14-10-2014, 04:57 PM
Charlie ring me later tonight and I will help sort this. Some of the reason why you can't get any joy is that the Motion controller plugin takes the functions away from Mach so changing settings on the screen as no affect.

charlieuk
14-10-2014, 04:59 PM
cheers thanks dean will do.

charlieuk
23-10-2014, 10:52 AM
Can any one recommend a water pump to use for my 2.2kw spindle that's sensibly priced. At present I have the coolant pipes going all the way to the control area so quite long but hoping this will help cooling.

Many thanks

Neale
23-10-2014, 11:05 AM
I use a cheap caravan water pump picked up off eBay for about 12 quid. It says it shouldn't be used for more than 15-20mins continuously, but I've wired mine to run off a switch giving either 5V or 12V; I use 12V to start for purging any air bubbles, and then switch to 5V for continuous running. It's done quite a few 6-7hour runs with no problem. The pump is in a bucket of water that I change from time to time. I know other people have much more elaborate solutions but simple works for me! No need for fans, radiators, etc, although that might depend on just how hard you are running the spindle.

charlieuk
23-10-2014, 11:27 AM
The spindle will be rarely doing any real hard work mainly cutting polystyrene it would be nice not to have to do anything to it though. Many thanks

EddyCurrent
23-10-2014, 11:52 AM
. . . it would be nice not to have to do anything to it though. Many thanks

I don't have a water cooled spindle but if I did this is something I would try.

Cold water header tank fed from mains water via ball cock, feeding small central heating pump (you can regulate the flow on these), return back to header tank.
Also an electric cutoff valve could be included, operated from the cnc control panel.
If the temperature got high I would include in the circuit a small central heating radiator, handy in winter.

GEOFFREY
23-10-2014, 03:17 PM
I don't have a water cooled spindle but if I did this is something I would try.

Cold water header tank fed from mains water via ball cock, feeding small central heating pump (you can regulate the flow on these), return back to header tank.
Also an electric cutoff valve could be included, operated from the cnc control panel.
If the temperature got high I would include in the circuit a small central heating radiator, handy in winter.

Eddy, i,m sure you could make that a bit more complicated if you really tried!!! G.

EddyCurrent
23-10-2014, 03:27 PM
Eddy, i,m sure you could make that a bit more complicated if you really tried!!! G.

Haha very good !, the thing is I had all those parts lying surplus (i.e. free) before Mrs. decided garage needed clearing out.

charlieuk
23-10-2014, 04:35 PM
Yea I'm know expert but I think that may be a bit over the top. The amount of surface area that 15m of tube has for the small amount of water inside and the temperatures we get over here and the load it will be under I don't think I will be fine just need to find a suitable pump that can run for a good few hours. I have been given a 240v pump that's destined for corrosive materials but can't help thinking its ott and going to be a waste of power?

JAZZCNC
23-10-2014, 04:40 PM
Charlie I've recently experimented with a 120mm PC radiator and fan with small PC pump with reservoir and it worked a treat thou I didn't cut with it for long and but did leave running at full speed for 6 hours and it hardly got warm.
I'm going to fit to my own machine and do some real world testing cutting aluminium when I get chance but don't hold your breath waiting.
If you want to try it then I'm 99% confident you won't have any troubles for what your doing and it will be very neat and travel with the spindle.

EddyCurrent
23-10-2014, 04:42 PM
Yea I'm know expert but I think that may be a bit over the top.

No way, those were just my first thoughts :hysterical:
If you get the extremes sorted out, the answer lies somewhere between.

charlieuk
23-10-2014, 05:47 PM
Charlie I've recently experimented with a 120mm PC radiator and fan with small PC pump with reservoir and it worked a treat thou I didn't cut with it for long and but did leave running at full speed for 6 hours and it hardly got warm.
I'm going to fit to my own machine and do some real world testing cutting aluminium when I get chance but don't hold your breath waiting.
If you want to try it then I'm 99% confident you won't have any troubles for what your doing and it will be very neat and travel with the spindle.

i have never heard of a pc water pump so put it in good old ebay and got this,thinking about it once the water is moving gravity will help it keep flowing especially if its a closed loop of water or with a small reservoir

http://www.ebay.co.uk/itm/SC-300T-DC-12V-Liquid-Water-Cooling-System-Brushles-Pump-Tank-For-PC-CPU-UK-Ship-/271595333604?pt=UK_HomeGarden_Garden_PondsWaterFea tures_UK&hash=item3f3c57e7e4

Clive S
23-10-2014, 07:13 PM
i have never heard of a pc water pump so put it in good old ebay and got this,thinking about it once the water is moving gravity will help it keep flowing especially if its a closed loop of water or with a small reservoir

http://www.ebay.co.uk/itm/SC-300T-DC-12V-Liquid-Water-Cooling-System-Brushles-Pump-Tank-For-PC-CPU-UK-Ship-/271595333604?pt=UK_HomeGarden_Garden_PondsWaterFea tures_UK&hash=item3f3c57e7e4
That's the sort of pump I used with less than a gallon tank with no problems but on your machine it might be better to have the pump etc on the z axis to get rid of the long hoses. You can buy a radiator for about 12 from China http://www.aliexpress.com/item/CPU-water-computer-water-radiator-cpu-water-cooling-90-small-water/975245718.html Remember winter is coming so antifreeze is a must. ..Clive

charlieuk
23-10-2014, 07:40 PM
Cheers thanks I will get one and see how it performs the silicone tube I have seams to get realy cool to the touch when it's full so try it and stick a thermometer in there. I will put a small amount of anti freeze in but it's in a well insulated room with that doesn't ever get down that low so no real worries of freezing many thanks

JAZZCNC
23-10-2014, 07:47 PM
To be honest I reckon if you use one of the wide Rads with twin 120mm fans then you'd get away with it no problems. Only reason I'm trying single 120mm Rad with fan is so can incorporate into Z axis cover and keep it all together but light at same time. Test's so far seem to show it will work and wit wide Rad so twice the cooling then I'm 99.9% sure it will work.

Edit: I even tried it with convection using no pump and while it worked felt it just not quite good enough.!

charlieuk
24-10-2014, 11:12 PM
Been playing about with a few bits like mounting the screen to the wall , putting the vfd screen on the out side of the box and also found a good use for round rail supports to make nice solid simple mounts for the proximity switches over my slightly crude aloy boxes.

charlieuk
29-10-2014, 01:05 PM
I'm having a few problems with my home and limit switches, I had a similar problem the last week but managed to sort it by adjusting it through the input signal filters in the csmio plug in however now I can't find the happy medium I found last time the video should explain the rest.

JAZZCNC
29-10-2014, 02:18 PM
Charlie are you using shielded wire for the cable back to control box and is the sheild earthed just one end inside the control box.?
Also is the machine frame earthed to same earth point.?

You have long wire runs so they will act like antenna picking up any noise so you'll need to Eliminate this really before you'll get any joy.
I would also try a differant switch you maybe have poor switch with slow components giving slow reaction times.?

EddyCurrent
29-10-2014, 02:29 PM
What do you have debounce set to in Mach3 General Config ?

charlieuk
29-10-2014, 02:59 PM
Yes it's all shielded at one end the Ali frame is directly bolted to the floor the moving part of the gantry though may not have any sort of ground unless it can travel through the Hiwincarriages. The problem seams to effect all switches. I was wondering about replacing a switch but wire it straight to the csmio ? Would it be best to disconnect the rest of them if I did that?

charlieuk
29-10-2014, 03:01 PM
What do you have debounce set to in Mach3 General Config ?
Zero would this be the same as the filter in the csmio plug in or have the same effect ?

charlieuk
29-10-2014, 06:41 PM
What do you have debounce set to in Mach3 General Config ?
I had a read up and I think it's a similar thing however it didn't seam to make any difference at all that I could figure I tried up to 4000.

JAZZCNC
29-10-2014, 06:49 PM
What do you have debounce set to in Mach3 General Config ?

Mach De-bounce isn't used with Csmio. More advanced Noise Filtering is done in the controller thru the Plug-in.

JAZZCNC
29-10-2014, 06:52 PM
Ali frame is directly bolted to the floor the moving part of the gantry though may not have any sort of ground unless it can travel through the Hiwincarriages.

Not to be trusted so run a Earth wire from both the frame and the Gantry back to the Star point in the Controller.

Clive S
29-10-2014, 06:55 PM
Yes it's all shielded at one end the Ali frame is directly bolted to the floor the moving part of the gantry though may not have any sort of ground unless it can travel through the Hiwincarriages. The problem seams to effect all switches. I was wondering about replacing a switch but wire it straight to the csmio ? Would it be best to disconnect the rest of them if I did that?When you say the ali frame is bolted to the floor that's OK but it would still need to be bonded the star point. Also what voltage are you running the sensors at. .. Clive

Edit the mistro beet me to it:star:

charlieuk
29-10-2014, 07:00 PM
Had a feeling that was the case jazz

thanks guys will do that and report back voltage at the switch is 23.9/24v

charlieuk
29-10-2014, 08:01 PM
Thinking about it then I really need to earth each of the axis? If so can I earth the z to the y then y to the main frame then back to the control box ?

JAZZCNC
29-10-2014, 08:09 PM
Thinking about it then I really need to earth each of the axis? If so can I earth the z to the y then y to the main frame then back to the control box ?

Charlie ring me I'll explain been in workshop since 6am drilling and tapping holes so can't be arsed to type all that's required as my fingers are killing me.!! Did try ringing you earlier today and just now but no answer.

charlieuk
30-10-2014, 12:55 PM
I have now earthed every thing together and it seams to have improved it in that the filter can now be set a lot lower however I still have the same problem. I did all so find one ferrite ring I put onto one of the signal wires at the control unit end but that didn't make any notable difference. What the best next step to take try some better switches?

EddyCurrent
30-10-2014, 01:50 PM
Set up the soft limits and slow zones, section 10.8 of csmio manual I'm looking at.
Mach3 General Config, try 'Home SW.Safety' in both states to see what happens.
Follow csmio manual section 10.11 and go through Mach 3 settings as shown.

charlieuk
30-10-2014, 02:02 PM
Set up the soft limits and slow zones, section 10.8 of csmio manual I'm looking at.
Mach3 General Config, try 'Home SW.Safety' in both states to see what happens.
Follow csmio manual section 10.11 and go through Mach 3 settings as shown.
Will take a look at that, just to let you know I have separate home and limit switches

charlieuk
30-10-2014, 02:47 PM
I took a look at all of the above and no luck so I have just taken a new switch and wired it straight in to the csmio and it would appear by just testing it by hand it cure the problem which would suggest that perhapsthe switch or the csmio doesn't like the long cables !

EddyCurrent
30-10-2014, 02:57 PM
long cables generally add capacitance and that will affect the signal, you can get low capacitance screened cable if you do a search.
As an experiment use some single core unscreened cable and temporarily wire the switch back to the input using that.

JAZZCNC
30-10-2014, 03:01 PM
I took a look at all of the above and no luck so I have just taken a new switch and wired it straight in to the csmio and it would appear by just testing it by hand it cure the problem which would suggest that perhapsthe switch or the csmio doesn't like the long cables !

It won't be the Csmio Charlie it will be a dodgy switch for sure. The Csmio are by far the best controller I've ever seen at handling noise, even my high frequency Tig welder doesn't bother them, no other Card I've used could handle this amount of noise.!

To test I've just connected one of those cheap prox switches to a 100mtr drum of cable which I put next to my VFD running at full speed and worked fine so i'd be changing the switch.

EddyCurrent
30-10-2014, 03:04 PM
To test I've just connected one of those cheap prox switches to a 100mtr drum of cable which I put next to my VFD running at full speed and worked fine so i'd be changing the switch.

What kind of cable ?

charlieuk
30-10-2014, 03:12 PM
Yea my guess is the Chinese switches too! Can you recommend any good ones? I looked on rs components but couldn't tell the difference they were between 20-50 each though! Would love to get some to try before the weekend though as tony is coming back down from Leicester to help tinker with it on sat. In the mean time I will swap the x limit swich and see if it's any better but I have a feeling they all need to be swapped to better ones

charlieuk
30-10-2014, 03:30 PM
I have just switched the x limit switch over to a new one and no difference so thinks it's going to need them all the way around. At least I will have some for a little machine I would like to do some time.

JAZZCNC
30-10-2014, 05:02 PM
What kind of cable ?

3 core CY same stuff I fit on machines and same stuff Charlie got on his machine I presume seen as I told where to buy it.?

charlieuk
30-10-2014, 05:11 PM
Yes it was from the link you sent. The only thing was that Tony used the pice of 12core I got to run accessories on to do all the switches so he used common + and - and then separate signals for each of the 6 switches. Should they all have there own separate screen cable which I do still have a roll of.?

firetrappe
30-10-2014, 06:06 PM
Dean - Just a thought, I don't know much about the CSMIO, but do you remember the issue we had with proximity switches and the PMDX? The BOB accepted both NPN and PNP switch inputs but was not auto detecting the correct type. We fixed it by adding resistors between the input terminals on the BOB. I doubt it's a similar problem, but just thought i'd throw that suggestion out there incase Charlie is using similar switches.

JAZZCNC
30-10-2014, 06:44 PM
Dean - Just a thought, I don't know much about the CSMIO, but do you remember the issue we had with proximity switches and the PMDX?

You having a laugh Si how could I forget that . . . . . . Cost me a nights sleep away from home and the remaining few strands of hair I had left. . Lol

Csmio inputs don't work like the PMDX and doesn't need to detect switch type as your free to use any logic at any voltage upto 30vdc. Your problem was with the PMDX rather than the switch and how it handles PNP logic.

firetrappe
30-10-2014, 08:27 PM
Oh well, it was worth a shot. I guess it's the switches then, unless the length of the wire runs are causing some issues. Might it be worth trying a spare switch separately on shorter wiring into the csmio to test?


You having a laugh Si how could I forget that . . . . . . Cost me a nights sleep away from home and the remaining few strands of hair I had left. . Lol

It was worth it though to see you dancing around my garden when we got it working though. (yes folks, Dean occasionally does a little dance when he's happy lol).

charlieuk
30-10-2014, 08:58 PM
Thanks for the suggestions anyway


so what do we think the next step is? Run a 3 core wire and try that instead of having them all together?

Try some different switch and if so which ones? Are Any from rs sutable as it would be handy so I could pick one up to try tomorrow.

EddyCurrent
30-10-2014, 09:06 PM
Thanks for the suggestions anyway


so what do we think the next step is? Run a 3 core wire and try that instead of having them all together?

That's what I suggested earlier but using single core wire. Capacitance acts like a time delay and that's what you are getting.
Better still use a piece of CAT 5 twisted pair, it's imunity to noise is good.

charlieuk
30-10-2014, 09:19 PM
That's what I suggested earlier but using single core wire. Capacitance acts like a time delay and that's what you are getting.
Better still use a piece of CAT 5 twisted pair, it's imunity to noise is good.
Sorry I must have missed that I will give it a try.

charlieuk
30-10-2014, 11:26 PM
We'll I tried 3 core shielded the full length and no luck I actually had to set the filter higher but still had the same effect. Running out of ideas, perhaps try a short run of cable just long enough to go straight from the box to the switch? Or try a different type of switch

charlieuk
31-10-2014, 10:13 AM
I'm not giving in! Just wired a short length of cable (2m) straight from the csmio to the same switch and it works perfect so I ether need to some how change the wiring or the switches.

EddyCurrent
31-10-2014, 10:18 AM
For limits I prefer this type, mechanical with a roller arm. I assume your Home switches are close to the control unit ?

http://www.ebay.co.uk/itm/ME-8108-Momentary-Rotary-Adjustable-Roller-Lever-Limit-Switch-/251515487831?tfrom=251487505330&tpos=top&ttype=coupon&talgo=undefined

Also looking at some earlier photo's I don't like the look of your 'target' for the sensor. It looks like a stainless cap head screw, try a piece of flat mild steel instead or a large steel bolt head for example.

charlieuk
31-10-2014, 10:28 AM
The home switches are all on the gantry the only or that could be made closer to the control box is the x home. The triggers are at the moment a stainless bolt in a alli washer I will try all steel now

charlieuk
31-10-2014, 10:39 AM
just tried just a steel bolt and it still had the fault

EddyCurrent
31-10-2014, 10:47 AM
just tried just a steel bolt and it still had the fault

Did it have a hole in the middle like the cap head screw or was it solid metal right across and at least the same diameter as the proximity switch ?

This is from Baumer inductive sensors catalogue.
Baumer

"Maximum cable length A large cable length is a capacitive load for the output circuit and increases the influence of interference. Length should therefore be kept as short as possible."

They don't quote a figure for max length though.

This is why I suggested using single core bits of wire just as a test over the distance, the capacitance is going to be low if they are kept well apart.

Save yourself the grief and fit mechanical switches for limits, you won't have these problems then.

charlieuk
31-10-2014, 11:14 AM
It was a m10 flat head bolt. The stainless bolt works fine on the short cable

JAZZCNC
31-10-2014, 02:01 PM
Save yourself the grief and fit mechanical switches for limits, you won't have these problems then.

But thats masking any issues not resolving them.! Charlies wire run isn't long, it's just longer than your average CNC machine but for industry 10-12mtr isn't long.
Mechaincal switches are OK for Limits I agree but what does he do then about Home switches.? . . Shouldn't have to put up with lesser accurecy by using mechanical switches.
I'm sure the problem lies with the fact these Cheap chinese switches obviosly don't like the longer wire run and any capacitance thats coming with it.! . . . . . That or he's got some other issue he isn't aware of yet.?

EddyCurrent
31-10-2014, 02:30 PM
But thats masking any issues not resolving them.!

No, it's about finding the right product for the job, I know that mechanical switches will be unaffected over the length of cable he's using, plus I'm trying to find a solution that's cheap and easy to implement. If Charlie want's to keep going to resolve the issues that's fine, I don't have a problem with that.


Charlies wire run isn't long, it's just longer than your average CNC machine but for industry 10-12mtr isn't long.

which is why we used these connected via stanadard armoured cable, okay up to 200m according to Schneider.

http://uk.rs-online.com/web/c/automation-control-gear/sensors-transducers/inductive-proximity-sensors/?searchTerm=telemecanique+inductive+proximity#esid =cl_4294967294,cl_4294574636,cl_4294957162,cl_4294 574595,cl_4294956105,cl_4294956147&applied-dimensions=4294572536,4294572538,4294863004,429487 6081



. . .but what does he do then about Home switches.? . . Shouldn't have to put up with lesser accurecy by using mechanical switches.

No, that's why I mentioned in an earlier post about his Home switches being near to the control box, it would make sense to have the Home position at that end.


I'm sure the problem lies with the fact these Cheap chinese switches obviosly don't like the longer wire run and any capacitance thats coming with it.! . . . . . That or he's got some other issue he isn't aware of yet.?

That is the best conclusion now, but with fault finding it's best to start with the easy things first and in the case of DIY, the cheapest too, and I don't like guessing, it's far better to work through logical steps then we all know the 'correct' answer if it comes up again.

JAZZCNC
31-10-2014, 03:05 PM
No, it's about finding the right product for the job, I know that mechanical switches will be unaffected over the length of cable he's using, plus I'm trying to find a solution that's cheap and easy to implement. If Charlie want's to keep going to resolve the issues that's fine, I don't have a problem with that.

Don't talk daft Man course it's masking the problem if you haven't found out why.!! Also you can't say proximity switches are the wrong product for the job of sensing it's what they are made to do for gods sake.! Only thing that could be questioned is the quality for intended application.


No, that's why I mentioned in an earlier post about his Home switches being near to the control box, it would make sense to have the Home position at that end.

That's ok for one axis what about the other Two. . ? Still got to accept lesser accurecy just to make it work M-Switch.! . . . Shouldn't and doesn't have to be that way.


That is the best conclusion now, but with fault finding it's best to start with the easy things first and in the case of DIY, the cheapest too, and I don't like guessing, it's far better to work through logical steps then we all know the 'correct' answer if it comes up again.

We started with Logical steps and eliminating obvious potential issues which don't cost money and now it's got to the point where it's time to swap components to see if fault or weak parts are the cause. Swapping out for inferior accurecy components shouldn't be even considered IMO. Esp with home switches.!!

EddyCurrent
31-10-2014, 03:24 PM
Don't talk daft Man course it's masking the problem if you haven't found out why.!! Also you can't say proximity switches are the wrong product for the job of sensing it's what they are made to do for gods sake.! Only thing that could be questioned is the quality for intended application.

You keep on about people picking you up wrong but now you're doing it yourself.

My conclusion is that it's capacitance of the cable so using mechanical switches is not masking it but using a product that will work in that situation.
I never said specifically that proximity switches were the wrong product for the job, but maybe 'those' ones are.
I know full well what sensors of all kinds are made to do having been in industry electricals for over 40 years.

I think the home switches will be okay because of the slow approach speed.

All other aspects I think are what is to be expected with DIY.

JAZZCNC
31-10-2014, 04:06 PM
You keep on about people picking you up wrong but now you're doing it yourself.

My conclusion is that it's capacitance of the cable so using mechanical switches is not masking it but using a product that will work in that situation.

No not really got it wrong at all.! Have you considered Your Conclusion is wrong.? Swapping for MS is masking the issue has the capacitance is still there and needs dealing with rather than avoiding (masking). Charlie as tried different cable and it's still there, was worse actually, yes could still be capacitance but I don't think so at only 12mtr length and 24Vdc. But my conclusion could be wrong also.?

The home switches are not Ok even at homing speeds this has been tried.! Also how can they be trusted if we haven't conclusively found the cause.?
Your method while yes maybe getting the machine working isn't the correct one IMO. It's still a mask for the real cause and who's to say this cause isn't going affect other aspects of the machine later down the line.? . . . .What if it is a wiring or grounding issue that isn't found now but surfaces at a later date when newness wears off or other attachments get added like probes etc which could suffer from same issue.?

Best resolved now and after all obvious causes have been eliminated then the next logical choice is to replace suspect components for same type or like in this case with same type but being of better quality. Changing to a compleltely diffeant switch type will in this case potentially mask some other cause or fault.!

charlieuk
31-10-2014, 05:02 PM
Thanks for all the input guys I went to rs but they didn't have anything suitable in stock and it would be 3-4 weeks the chap was looking at some by omron ? So unfortunately walked away with nothing. Tony has just found two to try from a place near him in Leicester and he is going to bring some micro switches down tomorrow as we'll just for a test per poses, hopefuly a second brain will help find out what's going on so fingers crossed. Many thanks for all the help it's much appreciated having people to bounce ideas around with.

irving2008
31-10-2014, 10:57 PM
The solution to the capacitance issue, if that's what it is, is to buffer the switches locally. It's not clear to me where the switches are located but a simple transistor or IC buffer would fix it at very low cost and could handle multiple switches if they are close together.

Jonathan
31-10-2014, 11:22 PM
The solution to the capacitance issue, if that's what it is, is to buffer the switches locally. It's not clear to me where the switches are located but a simple transistor or IC buffer would fix it at very low cost and could handle multiple switches if they are close together.

That's far too logical a suggestion for this discussion ;)

If charlie's keen he could put differential signalling ICs (e.g. MAX488) on both ends and may alleviate problems later on. They're low cost and easy to implement since the circuit's in the datasheet...probably excessive though so personally I'd try a transistor first as it'd take 2 mins to test.

charlieuk
01-11-2014, 01:32 AM
The switches are all on the gantry on the moving side of each axis, just let me know what I need to do to try your idea and I will give it a shot if I can get the stuff as I don't really understand what you are saying at the moment.

irving2008
01-11-2014, 03:59 AM
Ok, how many switches are there, what polarity (npn or pnp) and voltage? How are they currently wired?

charlieuk
01-11-2014, 06:31 AM
There are 6 in total 3 home 3 limit all pnp nc each one has a common + and - up to a junction box on the gantry were they go off on there own each have there own separate input wire on the csmio . the main wire is a 12 core cy screened and earthed at the control box all running on 24v

many thanks

Clive S
01-11-2014, 09:29 AM
Just for completeness (I am not familiar with the csmio) as this thread is long is the 24V ps -ve connected to the -ve on the controller board.

I would be very surprised if it turns out to be the switches although I favour npn type.
As has been said I don't think the cable length should be an issue.

Have you tried a small capacitor at the machine end of the ps supply cable across the +ve and -ve.

EddyCurrent
01-11-2014, 10:27 AM
I though Charlie had been advised which switches to use, but anyway for inductive proximity switches my advice would be 3 wire NPN, this is a useful thread Charlie; http://www.mycncuk.com/threads/7723-Which-Type-of-Limit-Switch?p=60012#post60012

JAZZCNC
01-11-2014, 11:17 AM
I though Charlie had been advised which switches to use, but anyway for inductive proximity switches my advice would be 3 wire NPN, this is a useful thread Charlie; http://www.mycncuk.com/threads/7723-Which-Type-of-Limit-Switch?p=60012#post60012

Unlike most Bob's the Csmio I/O's are not restricted on switch type or a set voltage/current so can use any Logic so PNP or NPN doesn't matter. NPN or PNP both do the same job they switch a circuit, just one sinks and one sources and the Csmio inputs accept either.
For instance input one could use PNP @ 6V and Input two NPN @ 24v provided they both have there own voltage source.

This one reason why it's used so often on retro fits as it can use Odd ball logic and voltages of Bespoke controllers etc.!

irving2008
01-11-2014, 12:34 PM
There are 6 in total 3 home 3 limit all pnp nc each one has a common + and - up to a junction box on the gantry were they go off on there own each have there own separate input wire on the csmio . the main wire is a 12 core cy screened and earthed at the control box all running on 24v

many thanksSo active low signal (i.e. break = limit/home hit), wired as per page 19 of the CSMIO/IP-M user manual?
.
I have to say I doubt line capacitance is an issue at the CSMIO end. CY cable is 75-150pF/m so looking at 900 - 1800pF for 12m. So when switch opens that 1800pF has to discharge through opto-isolator/resistor. Assuming standard 10mA opto current, series resistor is 2200ohm, so fall time is approx 6uS worst case. One simple & quick test would be to put an additional 2200ohm 1/2W resistor to ground at the switch end of the cable (or even a couple in parallel). This will discharge the capacitance faster and will reduce the effective capacitive load on the switch. Try that first...

EddyCurrent
01-11-2014, 11:25 PM
Watching the video more closely, when the plugin filter is reduced to 1 (video at about 2:49min in.) the switch works as expected but the auto reset won't work. So it looks to me like it's the input filter setting that is causing the problem with switch not triggering. The issue is then, why does it not reset when the limit override is selected.

From the manual.

"5. If the machine has entered the hardware LIMIT switch, you can leave it by switching on the Settings screen "OveRride Limits" button. It is also convenience to switch "Auto LimitOverRide" - this will cause that while the raid on SW limit switch the machine will stop , but you can click RESET and le ave the limit switches without any additional operations."

Is it saying that "Auto limitoverride" is for software limits (SW) ? and "Override Limits" button is for hardware limits ?

Charlie, set the input filter to 1 or zero and see what this "Override Limits" button is.

charlieuk
02-11-2014, 07:56 AM
Whew you set it to low when you hit the limit and then hit ether of the over ride buttons it triggers another e stop straight away so it it making it to sensitive. Like I said though when you shorten the wire it's fine and but I'm sure at one point I did have it going as is. We have some new switches to try so will be giveing that a go later

charlieuk
02-11-2014, 07:02 PM
Ok so we tried the new switch with not much improvement so tony put his oscilloscope on it and basically the large kinco driver for the x axis is putting out a huge amount of noise.

EddyCurrent
02-11-2014, 07:28 PM
The input filter in the plugin is used to stop spurious signals induced in the limits wiring acting as though the limit has been triggered when it has not.
If you are not getting these false triggers then the value in the filter setting needs to be as low as possible with zero being the best. Any higher setting is going to ignore the limit signal for a brief period of time and all that is demonstrated in your video.

It may be that noise is a problem once the limit has triggered but the main issue seems to be with resetting the system using some kind of override for the limits, I can't be more specific because I don't have access to a csmio board or plugin.
I do know that if you set up the software limits they should stop the machine before reaching the hardware limits and you should use those all the time, but obviously the hardware limits MUST be working for safety.

Are you using the most recent plugin software ?

charlieuk
04-11-2014, 10:35 PM
Just a quick update. We have managed to sort the problem which was noise being created by the x axis drive and the long cable. We first re did some of the earthing on various bits and put them in a nice brass terminal block which made quite a difference. We then swapped the cheap Chinese proximity switches for some made by Schneider which cost as much for one as 10 of the cheap Chinese ones (should have know better). The last step was adding a small resistor on the csmio end and it now all seams happy.we also got the PC water pump running and even on the long pipes it still pushes a nice flow of water. We have also fitted a relay so that it switches on with the spindle and dust extractor. Not quite to sure what is left bar finishing trying to set it up on mach3 and learning how to use mach3 and load g code ect. Again if there is anyone anywhere near Brighton that can help me learn how to use mach 3 that would be a massive help.

EddyCurrent
04-11-2014, 10:52 PM
Sounds like a combination of things, pleased to hear it's now working.

charlieuk
06-11-2014, 03:07 PM
We'll after a bit of trial and a lot of error I started to cut my first road runner. However the power socket trip out shortly after as I think I had to many things plugged in like a oil heater ect.

I now have two question, not that it worries me for this but would would you do if that happened on a big job?

And second the feed rate is really slow for cutting road runner in foam , I have increased it to max feed rate via the over ride on the main screen but it is still very slow so wondering were I increase it further? In the g code?

EddyCurrent
06-11-2014, 03:26 PM
I now have two question, not that it worries me for this but would would you do if that happened on a big job?

The problem is getting back to exactly where you were with regard to X,Y,Z zero positions. This is where Home switches come in, at least you can zero the machine coordinates with these, regarding work coordinates, when I've jogged the machine to where I want work zero X,Y,Z, I make a note of the corresponding machine coordinates from the Mach3 screen so if juice fails I can return to the same place. Maybe there's a better way but that's what I do because it's easy and understandable. You can then run the G code from the start or a line further on.


And second the feed rate is really slow for cutting road runner in foam , I have increased it to max feed rate via the over ride on the main screen but it is still very slow so wondering were I increase it further? In the g code?

Speed for rapids is set in Mach3 motor tunings, then feed speed is set with the F command in the G code, e.g. F800. You can override it while the G code is running using the slider on Mach3 screen.

charlieuk
06-11-2014, 03:34 PM
Cool will try adjusting it in the g code many thanks!

EddyCurrent
06-11-2014, 03:47 PM
Remember you might loose steps if you go overboard with it.

JAZZCNC
06-11-2014, 05:26 PM
Maybe there's a better way but that's what I do because it's easy and understandable. You can then run the G code from the start or a line further on.

Yes there is and it's really simple to do. Infact it's something you should get in the habbit of doing if long or important jobs just incase power or PC crashes.

Save the work offset. On the Standard Mach 1024 screen set you'll find it OFFSET's Tab on lower right under SAVE WORK OFFSETS.
On Gerry's screen you'll fing it on the small Tab offset's Tab again Save OFFSETS.
If you notice when you close Mach you get the message box "Fixtures Changed" and "Save Fixture" option this is the same as Saving work offsets.
See pics.
1381113812

Charlie the Road runner file uses Imperial measurements and if using metric units then while Axis scaleing will increase the size it doesn't change the feed rates so you'll need to do this manually by editing G-code.

charlieuk
06-11-2014, 07:21 PM
Cheers thanks for that I will try and figure that all out and get in the habit

ps dean I dropped you a pm

many thanks

charlieuk
12-11-2014, 02:30 PM
Still playing here and trying to work out mach 3. I'm not sure if the problems I am coming across are me or something not working right. I have watched all of the tutorials multiple times and trying to read bits of the manual but I suffer from bad dyslexia so reading is painfully hard and slow.

The first thing that doesn't seam to have any effect is the offline button, with it ether flashing or not the machine still responds to all commands as far as I can tell. Is there something else that has to be done to turn that on not that it's that important.

the second is if I run the road runner program the hit stop button what is the process to start back up again? the reason I ask is if I hit stop then jog a axis to the side to take a look then hit start it sometimes does not return to the last point were I stopped the cut and it starts else were ? it also does not re start the spindle however I assume that is normal and it has to be started manually?

I allso have have a problem with loosing power to the x and y axis , I'm still trying to figure if it's in mach 3 that's stoping it or if it's a fault on the drive which I am waiting to see next time it happens.

Many thanks

charlieuk
12-11-2014, 06:34 PM
I have been testing again and I'm wondering now if it's a setting to do with the arc when it moves between points however I still dong get why it's not starting back were it left off? The first pick I pressed stop jogged to the side and then hit go again. You can see the straight line were I did this and it did not return( centre of pic on his wing)The second pic I hit stop the pressed got to zero and then start and it did a similar thing?(going along his wing) Any ideas is it me or the machine?


Ps if there is anyone willing to give me a mach 3 lesson I would be happy to travel a way for it and pay if needs.

many thanks

Clive S
12-11-2014, 07:09 PM
The way I see it (and I am not an expert) is if you stop the machine and it was running on a curve it might not return to the same place. I would think you have to re start from a line number where it had been running a bit of G1 code .
I would try and experiment with some simple shapes like triangles and squares not circles.
and then try a feed hold and resume and then a stop then start ( I am not sure if pressing stop will lose steps)

If you have hit the E-stop button you would have to re home the machine ..Clive

charlieuk
14-11-2014, 10:07 AM
Many thanks will keep on playing.

Any by idea why offline does not work? Does it normally ?

Cheers charlie

JAZZCNC
14-11-2014, 12:22 PM
Many thanks will keep on playing.

Any by idea why offline does not work? Does it normally ?

Cheers charlie

Charlie Offline is a (Mostly) parallel port driver related function and the Csmio plug-in doesn't use it.! . . . .To be honest I've never used it EVER so don't see the point and wouldn't worry about it.

If you give me a ring then I'll walk you thru using Mach. To be honest Mach doesn't do much of anything other than move the machine and monitor inputs/outputs so when you have got it setup correctly and the basics covered you shouldn't have any trouble working it.
Think some of your trouble may be your not exactly setup right regards steps per and motor tuning. When this is correct then the rest will be easy with a little explanation.


I'm compleltely snowed under(Actually it's pissing down with rain not snow. . Lol) with work at minute otherwise would come down and spend some time with you.! Next time I'm down your way I'll let you know and call in for few hours.

charlieuk
14-11-2014, 02:29 PM
Cheers I was wondering if that was the case again with it, it's just not knowing these things and being my first time ect.

I will give give you a call but I will just wait until this new PC is here I'm hoping today or Monday and it's set up on that.
Many thanks

JAZZCNC
14-11-2014, 03:11 PM
Charlie just read your earlier post about not returning back to where it started from.? This could be the Step pulse edge is set on the wrong side in the drives so it drops a step with each direction change. This is easy checked and corrected.

To check just knock up some G-code for each axis that goes back and forth many times. Like Below.
G0 X75
x0
Copy and paste few dozen times into a file then Zero the Axis and make a mark to check if comes back to same spot then run the G-code.
Using Notepad then just do replace search and replace X with Y and repeat for each axis.

If it doesn't come back to the same spot then go into Ports and pins and toggle the Active Hi/low setting for the STEP to opposite state for which ever axis is wrong. This and the ENABLE setting are the only functions the ports n pins for motor outputs have on the Cslabs controller so ignore the rest.

EDIT: Other way to do it is thru the EM806 Drive software and changing the Active edge state but this is easier option.!

Blackrat
14-11-2014, 03:14 PM
when i started with mach3 i also found this rather unusual , that the machine wouldnt return to the point where i stopped it

but when you start to read G code and start to understand what i means, then it all starts to make sense

for example , when cutting an arc ( as mentioned ) and you stop the machine lets say 1/4 of the way thru the arc , when you restart , it will not resume from that 1/4 point thru the arc ... it will either start at the beginning of the arc , or the next line of G-code

the same with height, z - axis ... if im doing a cut , stop mid way thru and then RAISE the machine ... when i restart , the machine doesnt know that it been raised , and will only change the height when a line of gcode tells it to , so you may do an air cut for a few lines of code depending on what you cutting ....

if i stop and want to continue , i rewind a couple lines of code ...

and yes , you need to start the spindle manually ( again g code tells spindle to start right at the beginning of the code )

keep at it and it all starts to make sense .... :)

JAZZCNC
14-11-2014, 03:36 PM
for example , when cutting an arc ( as mentioned ) and you stop the machine lets say 1/4 of the way thru the arc , when you restart , it will not resume from that 1/4 point thru the arc ... it will either start at the beginning of the arc , or the next line of G-code

If machine is moving and you hit STOP then you really should presume the machine as lost position and Re-home. If you want to pause the machine and resume then you should use FEEDHOLD.
If machined is STOPPED and you want to resume from point in the G-code then use the RUN from HERE command. This will do a move back into position then pause with message asking for CYCLE START it will also give you option to start the spindle.
If using RUN from HERE then it's best done from the begining of Cycle or some position move in the code rather than half way thru canned drill cycle for instance.
RUN form HERE as saved my arse so many times I've lost count and use it all the time.

charlieuk
14-11-2014, 09:09 PM
If machine is moving and you hit STOP then you really should presume the machine as lost position and Re-home. If you want to pause the machine and resume then you should use FEEDHOLD.
If machined is STOPPED and you want to resume from point in the G-code then use the RUN from HERE command. This will do a move back into position then pause with message asking for CYCLE START it will also give you option to start the spindle.
If using RUN from HERE then it's best done from the begining of Cycle or some position move in the code rather than half way thru canned drill cycle for instance.
RUN form HERE as saved my arse so many times I've lost count and use it all the time.

Cheers guys yes blackrat sounds like the same thing I will re read this and try and process it.

are there any other learning tutorials that would help me learn this stuff? Cheers

charlieuk
06-12-2014, 02:12 PM
Just cut my first board and im really happy with how it went. A few things need to be worked on like a vacuum system which I have found does not need much power atall to pick up the light weight foam and also a way to hold the foam down at the corners and also allow some sort of accurate registration so when you flip the block it lines up perfect to cut the other side
( im looking for ideas here) I am also wondering if the motor on the x axis is way over kill as it is spinning quite slow even when at full speed and gearing it more will just produce more torque than I would need.

Blackrat
06-12-2014, 09:18 PM
gotta say that looks pretty good !

to locate the board ....

you have to have references cut into the foam block from the top side ... this is because the block is not accurate enough to flip over and carry on cutting

so instead of cutting the whole of the top of the block, id cut 6-8-10 (as many as you need to support the foam block) square patches into the block ... then when you flip the foam block over these machined patches locate onto the table by mean of MDF pieces that are the same size as the patch that was cut

hope it sorta makes sense :D

what software you designing the board in ?

charlieuk
06-12-2014, 09:47 PM
That does make sence and is a good idea I have been thinking along similar lines but drilling some large say 1" dia holes in the table then using the cnc to drill some matching holes in the blank and using a large dowl to locate. Like you say it would be nice not to have to worry about the block being perfect. I guess I should try both and see

Blackrat
06-12-2014, 09:53 PM
yup, thats exactly what im getting on at .... dowels in a blank that locate on the table sound good ... maybe machine round patches into the foam , and have the blank circular in shape

Blackrat
06-12-2014, 09:57 PM
summing like that ?

charlieuk
06-12-2014, 10:02 PM
Not sure I quite under stand ?

Blackrat
06-12-2014, 10:06 PM
I was just thinking you need more surface area in the foam block .or the dowel will press into the foam .... So machining a bigger circular shape provides this larger surface area

charlieuk
06-12-2014, 10:27 PM
I see what you mean I was thinking the dowels could be quite long and go almost all the way through the block, i think it would be stiff enuf then if I used large dowels. It doesn't need ultra high accuracy anything less than 1mm would be very nice. I'm kinda hoping the method I find i can do with out having to change cutters which is a huge 5"x 1 1/4 bullnose or spend too long having to machine things to set up. I think we are on the right lines though

charlieuk
18-12-2014, 02:35 PM
I have been doing some more test cuts with the machine, yesterday I was doing a cut and a bolt on the z axis rail came a fraction out and cased a jam however I was pretty quick at stopping it and I don't think there was any damage.

However today I have had a error come up that I think I have had before in that the z axis is getting a Stall Detection error on it ie 5 red flashes on the driver ( it is a leadshine em806 hocked up to a nema23)

This does not happen straight away it has been maybe 40 min into a job and the z axis has totally stopped, luckily it has stoped at a point were it has not ruined anything yet however I cant find any mechanical problem that would have caused a stall and I can re set the driver and all is ok again but odiously that's not a cure.

so first I need to figure why it is triggering the stall detection? any ideas????

then second is there a way to hock up a signal to go to e stop if this happens for any other reason. ( I have yet to look into this)

so a little confused at the moment, could it be more noise?

many thanks charlie

Clive S
18-12-2014, 04:04 PM
I think this can happen if the acc is set too high you can set the driver to send out an estop so that the complete machine will stop if any driver goes into fault. I think the signal has to be set up in the software of the driver. I am sure Dean will pop up with the correct way to do it. ..Clive

JAZZCNC
18-12-2014, 04:13 PM
I think this can happen if the acc is set too high you can set the driver to send out an estop so that the complete machine will stop if any driver goes into fault. I think the signal has to be set up in the software of the driver. I am sure Dean will pop up with the correct way to do it. ..Clive

Spoke to Charlie about other issue and why but you never mentioned the E-stop.!! . . . So Charlie it's easy enough to do. Tony will understand what to do.
The drives have fault output that you use to control a relay which is inline with the E-stop.
The fault signal Logic can be programmed in the drive so can be configured to suit your needs.

charlieuk
18-12-2014, 04:38 PM
cheers many thanks for the advice dean just ordered a few more pulleys to gear it down and will strip it all down this eve and see if I can find what's wrong and were the binding issue is. sorry I forgot to mention the estop thing as I was more focused on fixing the problem. toney is down next weekend fot Christmas so will get him on to it as he has been after things to play with.

many thanks

charlieuk
22-12-2014, 01:58 PM
I have changed to a 2:1 gear ratio and made sure it is all running smooth however I still seam to be getting the problem. I am just trying the job at 50% feed rate to see if that stops it. We are wondering if it happening when there is a fast change in direction and feed rate because of the heavy z axis. We think it is sways happening during a similar movement but not at the same point in time through out the job. Wondering if possibly we need to put a gas strut on the z or go up further on the gearing at the moment I have a 20t and a 40t

EddyCurrent
22-12-2014, 03:09 PM
then second is there a way to hock up a signal to go to e stop if this happens for any other reason. ( I have yet to look into this)

This is how I did it for the similar (I think) AM882; http://www.mycncuk.com/threads/6565-Ready-Steady-Eddy?p=57622#post57622

Contacts of the K2 relay would go in series with your emergency stop buttons

charlieuk
22-12-2014, 03:22 PM
just to add to thins the weight of the z axis is aprox 14kg and its on a 1605 screw and a 3nm nema 23. I ran it at 50% and it actually cut out sooner. I have got another set of pulleys coming which will give a 3.8:1 ratio so hoping that may help and in the mean time Im going to try taking of the spindle to reduce the weight and see what that does.

JAZZCNC
22-12-2014, 04:30 PM
just to add to thins the weight of the z axis is aprox 14kg and its on a 1605 screw and a 3nm nema 23. I ran it at 50% and it actually cut out sooner. I have got another set of pulleys coming which will give a 3.8:1 ratio so hoping that may help and in the mean time Im going to try taking of the spindle to reduce the weight and see what that does.

Charlie from what you told me regards velocity and Acc settings being so low and with 2:1 ratio then it should handle the weight without stalling or missing steps.
When my machine was vertical the gantry was much heavier than 14Kg and a single 6Nm nema34 which turned twin 5mm pitch screws via belts that where geared 1:2 to give speed so actually lowering torque by aprox half easily moved gantry. This means you actually have more torque than I do.!

If your absolutly sure there's no sticktion on the linear motion side then Things to check First is if the motor is wired correctly and performing properly.? Have you wired it in parallel or series.?

With 3.8:1 ratio you will be quite low on speed and Acc you'll reach which for 3D work you may want.? So I would try to find the cause.
Counter balance/Strut arrangement can't hurt if you have room to fit so I'd do this any way just to help take the the strain.

charlieuk
22-12-2014, 06:34 PM
I'm prity sure all is sliding ok. The z axis would fall nearly the hole way under its own weight with the belt removed from the stepper and with the spindle removed it was still triggering. I have since got the screw a hair better by shiming it .10. We did adjust the speeds this morning with the gearing but we have backed the acceleration back again and running another test now

charlieuk
22-12-2014, 06:55 PM
I forgot to say the steppers are in parallel

charlieuk
22-12-2014, 09:49 PM
Ok so the final test we did this eve was to swap the drivers over for the y and z which are the same and also slowed the acceleration down further to 150 and this managed to run through the hole cut without stoping so tomorrow we will switch the drives back and keep the acceleration the same and see if that is still ok. What we did notice though is that the steppersare getting quite hot (45-50 deg) Im not sure if it is directly linked to the problem as it happened on the first test of the day but it spears that they need to be set to run cooler? Is it because they are set in parallel and not running very fast? Although I have a lot of travel the y and z only travel very small amounts at a time when cutting a board.

JAZZCNC
22-12-2014, 11:07 PM
That's not hot for steppers so don't worry too much about it. Esp if they are moving slow rather than stood still as they will be using full torque to hold position
and not going into current saving mode.

Are you sure the drives are set correctly regards Amps and motor setting.?
What number or letter is the dial set to on the drives.?
Have you tuned the drives using protune or just using the dip switches.? If not try to use protune and make sure the amps are set correct for the motors. Wrong amps setting would cause this problem and the drives default to a low setting if I remember correctly. If you have the wheel set wrong on the drive it will think it's using differant motors and can default to low amps setting and wrong PID tuning in the drive.
Do the motors make any whistling or loud buzzing sounds.?

150 on acc is far too slow for any z axis and you should be able to go much higher without any trouble. So this must be either your set wrong in the drives or there's binding at some point.!

charlieuk
22-12-2014, 11:37 PM
Ok that's good to know regarding temp, I will look at the settings tomorrow but we have them just set on the closest setting on the switches at the moment as I didn't really understand the pro tune. I will try and down load it again in to the new computer and see if it makes any more sense now I know a little more. The motors are quiet and don't seam un happy. I will be back with more info in the morning many thanks for the help

charlieuk
23-12-2014, 02:09 PM
These are the settings I have for the z. I am struggling to load a driver for the USB to 232 cable for windows 8 that I got from zapp. The cd it came with says windows 8 but it's all in Chinese. We have just swapped the drivers back and re running the file to see if the problem comes back