PDA

View Full Version : BUILD LOG: New Build 1000x600x200mm (newbie)



Noplace
21-01-2015, 12:59 PM
Hi Everyone,

first let me say that I'm a total noob compared to you all but willing to learn if you guys advise me.
I have already bought parts based on recommendations from this forum and have the design in my mind and hopefully will state all my plans here. I'm sorry I'm not a pro in using cad programs so I can't show you any designs but that's something I'm planning working on.

My extent of experience in CNC machines is building up a shapeoko2 (upgraded to 1x1m) with stock parts, though that machine is doing well for what it is, I wan't to make my own rigid machine.

My main aim is to be able to cut guitar body parts from wood like alder,maple,basswood etc.
Being able to cut alum/acrylic/plastic for projects would be a big plus, and achievable I imagine.

based on my requirements I decided on this size as I don't see me needing more than that work area (even less) and would happily trade the extra size for more precision/accuracy,stability and rigidity.


this is just a placeholder, will post more

Thank you!

kingcreaky
21-01-2015, 05:25 PM
Hi Noplace

Download Sketchup; its free

there are LOADS of videos all over youtube showing you how to do everything... bit of patience and you'll get there

you'll be so pleased youve learnt it aswell.. its so useful for so much other stuff


keep us posted...

njhussey
21-01-2015, 05:31 PM
Good luck with the build, always makes me nervous when someone posts that they've bought parts and they've not posted a design for all to critique....

With regards to drawing, Sketchup is free and good for playing about so you can see how things might go together.

Noplace
21-01-2015, 07:49 PM
Thanks for the Sketchup suggestion, I have dabbled at it before but ill give it a more focused go now.

I kinda thought that buying parts before design is frowned upon here, but I really didn't have a choice unless have to wait until I Become good in designing software, but I had no patience for that and was eager lol.


Material/Parts so far:


2x HGR 35mm Rail : 1000m & 2 x 35mm Bearing Block, Square
2x 40mm x 80mm T-Slotted Extrusion : 1000m
2x 80mm x 80mm T-Slotted Extrusion : 600m
4x 40mm x 40mm T-Slotted Extrusion : 600m
Assorted brackets, nuts and screws for the above
2x 1610 Ballscrew : 900mm & 2x Housing Bracket
2x BK12 & BF2
2x Flexible Coupling Coupler 6.35mmx10mm shaft
2x NEMA 23 Stepper Servo Motor Mount Bracket
4x SY60STH86-3008B Nema 23
1x Leadshine EM806
1x C35S - QUICK SETUP BREAKOUT BOARD (C35S)
1x RPS608 Power supply


Once I get all the items I will lay them out and take photos of how I plan on building and hopefully you guys could contribute on any required adjustments

you would notice I still didn't buy anything for the gantry as I have still not designed it (in my mind lol) and have to procure the side plates which I really need help with.

I'll get more drivers once I configure the first one, would need help with the wiring with the power supply,is it enough to drive 4 of them?

Thanks!

EddyCurrent
21-01-2015, 10:20 PM
I'll get more drivers once I configure the first one, would need help with the wiring with the power supply,is it enough to drive 4 of them?

Thanks!

Probably not big enough for the job 10 amps would have been better, read this; http://www.geckodrive.com/support.html
Now you have it I would give it a go and see how it performs.

Boyan Silyavski
22-01-2015, 11:13 PM
2x HGR 35mm Rail : 1000m & 2 x 35mm Bearing Block, Square


Now you have got me here. Quite big, don't you think? Normally 20 size is enough.


By the way i have always wondered:what is the size router the guitar makers need? It seems you can clear that question now.

Noplace
23-01-2015, 03:59 AM
2x HGR 35mm Rail : 1000m & 2 x 35mm Bearing Block, Square


Now you have got me here. Quite big, don't you think? Normally 20 size is enough.


By the way i have always wondered:what is the size router the guitar makers need? It seems you can clear that question now.


I chose that based on what I read from the product document, thought might be better take something better than to be sorry, would it cause any issues?

as router I'm no expert but I know some are using ones like dewalt and bosch colt.

Noplace
23-01-2015, 04:44 AM
Motors and driver arrived, just waiting for power supply and breakout board to test them out.

Now the big questions:
-what would be the ideal setting for the drivers? amps and microsteps?
-whats the correct wiring for the motor and driver? series/parallel/other?
-what type of connectors and cables should I use to connect motor and driver ? 18awg 8conductor? ethernet cables?? please point me to a site that sells good ones or is normal cat5/6 sufficient?

edit: sorry I kinda felt dumb asking the last question, now I understand that the 8 wires from the motor would be paired so the cable should be 4 core as stated in other posts. and I guess ethernet is ok for connection between stepper driver and breakout board?

however what would you recommend to connect the motor cable? straight up soldered into the long 4-core or connectors?

http://www.mycncuk.com/attachment.php?attachmentid=14493&stc=1

Boyan Silyavski
23-01-2015, 08:09 AM
I chose that based on what I read from the product document, thought might be better take something better than to be sorry, would it cause any issues?

as router I'm no expert but I know some are using ones like dewalt and bosch colt.

i mean the working area needed for guitar making ?

Noplace
23-01-2015, 09:55 AM
i mean the working area needed for guitar making ?

guitar body blanks are around 482x355x45mm so I should have plenty of space, even for the necks but I think thats more advanced

EddyCurrent
23-01-2015, 09:58 AM
i mean the working area needed for guitar making ?

If you want to make a through neck bass or 8 string guitar without having to move the blank in between machining, the work area needs to be 1200 mm long, the 600 wide is okay.
But because the neck would need to positioned more carefully it makes sense to move the blank into a different position than the body was in, so 900 mm long would be okay.

EddyCurrent
23-01-2015, 10:07 AM
however what would you recommend to connect the motor cable? straight up soldered into the long 4-core or connectors?

Yes, solder then cover each joint with heatshrink sleeving. Then solder a piece of wire about 200mm long, of the same thickness as the core wires, to the screenm then cover the whole area with a larger piece of heatshrink. Now you should have all the joints covered and that 200mm piece of wire coming out from under the large heatshrink sleeving and that wire is used to earth the screen.

Clive S
23-01-2015, 10:15 AM
Yes, solder then cover each joint with heatshrink sleeving. Then solder a piece of wire about 200mm long, of the same thickness as the core wires, to the screenm then cover the whole area with a larger piece of heatshrink. Now you should have all the joints covered and that 200mm piece of wire coming out from under the large heatshrink sleeving and that wire is used to earth the screen.Just for completeness I would suggest 4 core CY 1mm or 1.5mm cable as http://www.csecables.com/acatalog/CY-Cable-4-Core.html .. Clive

Noplace
27-01-2015, 10:18 AM
Just started learning solidworks, please bare with me I'm a total beginner in this thing but somehow managed to design the frame as I intended based on the parts I bought:

http://www.mycncuk.com/attachment.php?attachmentid=14528&stc=1

Noplace
29-01-2015, 08:46 AM
Here is my design of the gantry side plates, the hiwin blocks are actually longer and would be mounted at both ends and not like the design below, I just couldn't find the right CAD model for the HGH35CA

the plates are 10mm thick and they would attach from the bottom outside to the ballscrews ( again sorry I couldn't find the proper CAD models, really new to this and self learning)

http://www.mycncuk.com/attachment.php?attachmentid=14537&stc=1

Guys I could really use some advise and guidance at this stage, really appreciate it.

Also if anyone is a solidworks expert, I couldn't figure out a way to mate the left and right linears, maybe it will show in the photo that they are not exactly aligned.

EddyCurrent
29-01-2015, 10:36 AM
If the gantry side plates are aluminium then 20mm thick is the usual advice.

Blackrat
29-01-2015, 01:03 PM
use parallel mates to hold the bearings on the rails ... then use co-incident mates to hold the 10mm plates onto the bearings
you also use a coincident mate to keep the front faces of the two bearings aligned, so when move the one gantry arm, the other will follow

Noplace
01-02-2015, 09:48 PM
Updated with 20mm plates and a bit of the gantry, do you think it would need more support or can i stick with just the two 40x40 extrusions?

http://www.mycncuk.com/attachment.php?attachmentid=14578&stc=1

njhussey
02-02-2015, 11:21 AM
Hi Noplace, your frame needs a lot of bracing and strengthening as does your gantry. Have a look through some of the build logs and you'll see what I mean....these are two sililar to what I think you're aiming for?

http://www.mycncuk.com/threads/6988-routercnc_MK3

http://www.mycncuk.com/threads/8206-Ar-last!!!-Started-my-Gantry-3-Axis-CNC-Build

Noplace
02-02-2015, 12:03 PM
Hi Noplace, your frame needs a lot of bracing and strengthening as does your gantry. Have a look through some of the build logs and you'll see what I mean....these are two sililar to what I think you're aiming for?

http://www.mycncuk.com/threads/6988-routercnc_MK3

http://www.mycncuk.com/threads/8206-Ar-last!!!-Started-my-Gantry-3-Axis-CNC-Build

Hi many thanks for your comment, yea the 2nd link looks more or less like what I'm aiming. as you see in my design the frame ends consist of 80x80 extrusions but I left out 3 pieces of 40x40 which I will attach through out the empty space, I do think that would be enough support and I hope I'm not wrong hehe, otherwise I could get more and enforce further?

for the gantry I guess I still didnt settle on a design in my mind, maybe instead of the 40x40 extrusions I would replace them with 80x80? I apologize I'm not a mechanical engineering just going by my own logic so not sure what else I could add to it to make it better

njhussey
02-02-2015, 04:10 PM
The most common configuration for a gantry is the L shape. Mostly others use either 80x40, 90x40 extrusion or 100x50 rectangular box section aluminium. There are any number of threads showing this examples such as any of Kingcreaky's 3 builds, Eddy Current's build etc. etc. have a look at these and you'll see the type of thing.

Noplace
05-02-2015, 09:06 AM
Hi, what do you think of this brother?

http://www.mycncuk.com/attachment.php?attachmentid=14589&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14590&stc=1

Boyan Silyavski
05-02-2015, 09:28 AM
What Z axis height /work piece/ you are trying to achieve? The gantry seems too high, not sure, may be the perspective on the drawing. For this type of machine 100mm is reasonable, 120mm is best compromise, 150mm is on the limit and more than that is just wishful thinking. Without further reinforcing the gantry with say - a steel plate.

Noplace
05-02-2015, 09:50 AM
Hi yeah I think you are right it does look way too high, I have reduced it by 100mm which would look like this now :

http://www.mycncuk.com/attachment.php?attachmentid=14595&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14596&stc=1

changed to perspective projection that might look more realistic I hope.

I was really hoping to achieve more than 100mm z-height, but if I can stretch it to 150mm I guess that would be okay.

njhussey
05-02-2015, 09:54 AM
The best and stiffest way to achieve height is to have the L shaped gantry sitting on the carriages and raise the frame up on legs. If you have an adjustable bed then you can cut deep items but for 90% of cutting have the bed as near the cutter as possible to keep cutter flex to a minimum. What will you be mostly cutting?

Noplace
05-02-2015, 09:57 AM
Hi Neil, mostly wood with occasional aluminium

Noplace
02-03-2015, 08:49 PM
hey guys I could use your help on designing the Z axis to complete the machine, I have made it 200x240mm but I don't know if that is the best size given my machine overall design.

and am thinking of mounting the hiwin blocks on the stationary part and the rails on the second plate which will move up and down, should the second plate and the rails be also 240mm ?

last thing i need help with (for now lol) is what HIWIN rail and block size should I use for my x axis ( gantry left and right ) and z axis? HGR the heavy duty ones or will EGR be good enough?

thanks !

http://www.mycncuk.com/attachment.php?attachmentid=14770&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14771&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14772&stc=1

Noplace
02-03-2015, 09:03 PM
I forgot to mention that I'm planning on using 2.2kw Chinese spindle and won't be changing that in the future for this machine, the bracket for that is 150mm I think, so should I reduce the Z plates width to 150 or stick to 200?

routercnc
03-03-2015, 02:06 PM
In terms of width of Y axis plate then 200mm is reasonable to reduce racking of the Y/Z axis assembly as this spreads the Y bearings apart a bit. Some people make the plate have 'ears' where the Y bearings mount which can help with clearance and assembly. Not mandatory as it depends on the other details of the design, but worth a look.

I went with less than 200mm spacing to get more working space as it is primarily a wood cutting machine. There is no problem with mounting a 150mm wide plate to this to hold the spindle. You can use the real estate at the sides to mount DTIs, laser pointer, dust shoe etc.

In terms of height of the Y axis plate only needs to be as high as the Z ballscrew, fixed and floating bearing, and stepper connection dictates. You need to draw these to see how tall it has to be to give the required travel on the Z ballscrew nut. In practise this could be close to 240mm but there is no specific requirement to match the moving Z axis plate in height.

Bearing sizes - I used 15mm on the Z (but wish I'd used 20mm as they are much stiffer), 20mm on the Y (which I'm happy with) and 16mm SUPPORTED rail on the X (wood cutting machine). If I was to use profile Hiwin style rail then I would use 20mm as a minimum.

The way you have mounted the gantry to the X bearings looks poor, as seen in the front view picture. A very long cantilever plate which is OK for wood, but not ideal for aluminium. You should redesign this, or add a further connection up to the gantry, or raise the X axis to meet the gantry directly.

JAZZCNC
03-03-2015, 04:02 PM
Well with the Y axis rear plate(across gantry) you have room to have it wider than the front plate because it will over hang the bearings which the front plate can't or will crash into bearings. This will make Y axis much stiffer and be easier to access the bearing bolts. Yes put the bearings on the rear plate, rails on front moving plate.

For the Z axis you want hi-win HGH20CA Z0 which are the slim type and for the other Axis you want HGW20CA Z0 which are the wider bearing and will give a bit more support. Don't use 15mm the bearing blocks are too small and fiddly making building a Z axis more difficult due to clearences etc.

With the design I feel you are a little low on the height as it won't leave much room for cutters but then again I don't know what your cutting so may not matter.
Neils suggestion about X bearings looking poor is valid and has it is will need some bracing to help stiffen which is easy enough. But there's another change that I would make which will lessen the cantilever but more importantly allow for easier adjustment of the ballnut and allow some protection for the screws.?

Make the Gantry sides drop to the inside of the ballscrew not the outside.? This will shorten the gantry width and reduce bearing plate width and cantilever making it stiffer.
It allows access from the outside to the ballnut for adjustment and greasing etc.
Another important and often overlooked thing is screw protection, Your way makes it harder to protect the screw with a cover because of the gantry side being on the out side. If it's on the inside if the screw you can make a cover using C channel with a brush strip on top that covers any gap and wipes the gantry. This makes a very easy way to cover and protect which you'll want to do if cutting aluminium or wood even with screws on outside. (see pic)
1478214783

njhussey
03-03-2015, 06:28 PM
Make the Gantry sides drop to the inside of the ballscrew not the outside.? This will shorten the gantry width and reduce bearing plate width and cantilever making it stiffer.
It allows access from the outside to the ballnut for adjustment and greasing etc.

Make sure that you also think about how you are going to mount things like the ballscrew housings on, for example, the gantry sides.....(cough....don't ask me how I know!!) I'm using MGD16 ballnut housings which you can mount from the outside of the gantry endplates instead of some lower profile aluminium ones that I got from Aliexpress which I would have had to mount to the gantry side and then put the side on the gantry..............:victorious:

Noplace
03-03-2015, 07:22 PM
gents thanks a lot, I'm going to change a bit to make it more rigid, I have an idea on my mind I'll work on, I just hope its good enough :black_eyed:

Noplace
03-03-2015, 07:40 PM
I made a quick change to the gantry sides , reduced the width since its just going to be a waste with unnecessary cost and also hindering rigidity. gantry sides are now inside, will have to figure how to design the ballscrew holders with this design, but at least its not compromising (hopefully)
http://www.mycncuk.com/attachment.php?attachmentid=14790&stc=1

Clive S
03-03-2015, 07:48 PM
Try and keep the gantry sides all one piece like Jazzcnc first pic. Clive

njhussey
03-03-2015, 07:48 PM
Just have the sides going straight down like Jazz showed in his last post, you're making it uneccessarily complicated. To make the gantry really stiff ideally you'd drop it so it sits on the plate the X axis carriages...

(Clive beat me to it...)

JAZZCNC
03-03-2015, 09:26 PM
What Profile are you using that those rails sit onto because the rails look nearly as wide as the profile which if 20mm or 30mm the profile it is far too weak.

That or things are very much out of scale which makes designing very difficult.!

Your change is weak and complicated so I wouldn't take that route.

Noplace
04-03-2015, 04:07 AM
What Profile are you using that those rails sit onto because the rails look nearly as wide as the profile which if 20mm or 30mm the profile it is far too weak.

That or things are very much out of scale which makes designing very difficult.!

Your change is weak and complicated so I wouldn't take that route.

It's 40x80mm

Noplace
04-03-2015, 04:42 AM
How does this look?
http://www.mycncuk.com/attachment.php?attachmentid=14793&stc=1

JAZZCNC
04-03-2015, 10:26 AM
How does this look?

Much better but again you don't have much clearence between base and lower gantry so just becareful you don't limit your options.
What size are those rails.? They must be 30mm if profile is 40 and 30mm is massive OTT.

You havent shown a view with how the bearing plates fit with regards gantry cross piece, don't get caught out with common Gotcha of not beaing able to get to bearing bolts.!!

With you have such short travel distance then I change my statement about having Z rails on front plate. With this short stubby design you'll be better with them on the rear plate as you will hardly ever extend below the bottom of the rear plate when spindle is attached. In this case you'll need to go up more than down for tool clearence so you may need longer rear plate.

I suggest you continue with design and draw in the rest of the Z axis with spinlde to get an idea of what cut travel you'll have available.

Noplace
05-03-2015, 07:19 AM
unfortunatly like an idiot i bought the rails 2 months ago while having a vague idea of what I want, so I have to work it in.

working on the design, just a quick update on the side showing how the rails and ballscrew work together, i had to redesign a bit:

http://www.mycncuk.com/attachment.php?attachmentid=14813&stc=1

njhussey
05-03-2015, 08:17 AM
How big are the bolts for the rails? Will they fit in the profile that you've drawn? As Jazz says the profile is looking a bit small and weak, you could do with beefing them up a bit. It's looking like you're putting the Y axis ball screw on the front of the gantry, you'd be better putting it on the back and bringing your spindle nearer the front of the Y axis otherwise it could be quite a way off the front and a way in front of the X axis bearings. Are all the rails the same size?

Boyan Silyavski
05-03-2015, 09:06 AM
What Dean is saying is you have very small clearance from gantry to bed. You need sth like 230mm distance for a 200mm Z axis travel, if well designed. Do you have that space as drawn?

Noplace
05-03-2015, 09:29 AM
I'm adjusting to lower Z depth, around 80mm would be ok for me

Noplace
05-03-2015, 09:31 AM
How big are the bolts for the rails? Will they fit in the profile that you've drawn? As Jazz says the profile is looking a bit small and weak, you could do with beefing them up a bit. It's looking like you're putting the Y axis ball screw on the front of the gantry, you'd be better putting it on the back and bringing your spindle nearer the front of the Y axis otherwise it could be quite a way off the front and a way in front of the X axis bearings. Are all the rails the same size?

can't I just reduce the space I reserved at back of gantry from 80mm to 40mm? so that the plates and spindle come within the bearing range

Noplace
07-04-2015, 05:59 PM
Hey everyone, I'm in the process of redesigning the gantry and need your input, I will probably need to use pulley and belt for both Y and Z based on the new placement of motors.

can you please help me in figuring out the belt length I require based on distance between motor and ballscrew? I prefer 1:1 ratio and based on what was recommended to me I think HTD pulley 5mm pitch 15mm width is good?

many thanks, will try to post design photos soon

Boyan Silyavski
07-04-2015, 07:11 PM
can you please help me in figuring out the belt length I require based on distance between motor and ballscrew? I prefer 1:1 ratio and based on what was recommended to me I think HTD pulley 5mm pitch 15mm width is good?



Here is the belt length calculator , sorry, busy now but later will take a look if nobody does before

http://www.product-config.net/catalog3/d/bbman/config.html

Noplace
07-04-2015, 09:09 PM
thank you very much!

Noplace
08-04-2015, 07:05 AM
Just a preview render, if you have comments please let me know.

Based on center distance I got around 292.2mm belt length, but in the site it says next available length is 295mm , i assume that is a standard length increment across all vendors, so is it ok to get that length ?

http://www.mycncuk.com/attachment.php?attachmentid=15114&stc=1

Clive S
08-04-2015, 08:41 AM
You will need to put slots in the motor mounting to enable you to have adjustment to tighten the belt. It is quite normal to have 30 - 40 mm adjustment. >clive

Boyan Silyavski
08-04-2015, 09:37 AM
You will need to put slots in the motor mounting to enable you to have adjustment to tighten the belt. It is quite normal to have 30 - 40 mm adjustment. >clive

The slots need to be 1mm wider than the OD of the motor mount hole. Some servo motors will not allow that movement because the center part is bigger than nema 23 for example, but i can assure you that even 5 mm possibility to move is ok if you use that calculator. Just tested that theory with my servo motor mounts where it was not possible more play. So on a Nema 23 +-10mm both side from center hole is more than enough. Care should be taken if the mount is milled deep into a plate and the motor needs more play just to pass through and enter at its spot.

Clive S
08-04-2015, 10:06 AM
The slots need to be 1mm wider than the OD of the motor mount hole. Some servo motors will not allow that movement because the center part is bigger than nema 23 for example, but i can assure you that even 5 mm possibility to move is ok if you use that calculator. Just tested that theory with my servo motor mounts where it was not possible more play. So on a Nema 23 +-10mm both side from center hole is more than enough. Care should be taken if the mount is milled deep into a plate and the motor needs more play just to pass through and enter at its spot.The reasoning behind the 30mm is to allow for the possibility to change the pulley ratio if needed. ..Clive

JAZZCNC
08-04-2015, 10:39 AM
The reasoning behind the 30mm is to allow for the possibility to change the pulley ratio if needed. ..Clive

And excellent reasoning dear Sir. . :applause:

routercnc
08-04-2015, 03:12 PM
I think what silyavski is saying is that the centre hole on a nema 23 needs to be about 40mm dia to clear the 38mm raised boss on the end of the motor. If you cut long slots for the motor mounting then as these are about 47mm apart and about 6mm across then they get very close/ too close to the centre hole. On a servo motor this overlap sound like it is worse (don't own servos myself)
If you need a long adjustment slot (more than +- 10mm) a workaround could be to lightly pocket the 40mm centre clearance instead of a complete cut out ? Away from computer so can't check this for sure. Is there another way?

njhussey
08-04-2015, 03:27 PM
The centre hole on a Nema 23 gets awful close......well actually this close:

15115

It's actually thinner on mine now than shown in the picture as I tapped the stepper flanges M5 and machined the slots 5.5mm instead of 4.5mm.....

http://tapatalk.imageshack.com/v2/15/04/08/5cb9e9304670e90dd1ab08c43aba6d23.jpg

Boyan Silyavski
09-04-2015, 11:36 PM
I think what silyavski is saying is that the centre hole on a nema 23 needs to be about 40mm dia to clear the 38mm raised boss on the end of the motor. If you cut long slots for the motor mounting then as these are about 47mm apart and about 6mm across then they get very close/ too close to the centre hole. On a servo motor this overlap sound like it is worse (don't own servos myself)
If you need a long adjustment slot (more than +- 10mm) a workaround could be to lightly pocket the 40mm centre clearance instead of a complete cut out ? Away from computer so can't check this for sure. Is there another way?


Exactly thats what i meant. Thanks!

There must be many ways to do a thing but here is how i think:

-more or less center to center around 90mm, so that usually the belt is in the region of 270 to 315mm depending on the ratio.

-Dont have the time now to play and prove it but at that distance/look at the Nema 23 mount/ was possible to lower the small pulley teeth count and rise the other , so as i remember 1:1 to 1:2 was possible may be even more, without changing anything. I just remember that when doing the yellow machine there was that consideration also.
Same with the servo machine now i am building but not to such extend, due to shorter play possibility.

Below you will see a picture with the maximum movement according to me and having in mind the parts were laser cut from steel. So maybe from aluminum could be more play.

Nothing to prove with all that , just sharing for your consideration and if possible to help avoiding errors. Thanks


PS. The measures are radiuses, possible play and size of the thinnest part there

http://www.mycncuk.com/attachment.php?attachmentid=15121&stc=1

Clive S
10-04-2015, 01:03 AM
Neil It is close but it works OK of course you can put washers on the cap heads to spread the load.

Silyavski Another way would be to mount the motor on to a plate with no adjustments and then mount that plate with slots on top of another plate so that the motor and its plate would be adjustable. ..Clive

JAZZCNC
10-04-2015, 11:53 AM
Nema 23 Boss is 38mm-/+0.1 the whole point of the boss is to have close fit to stop movement so making 40mm hole is wrong way to go aout it. 38.3mm usually is just enough for nice snug fit. When done this way then there's no problem with slots or mounting holes if again they are milled to correct size also.!

IF you don't have room for slot adjustment then use an idler gear to take tension up. Not ideal way to do it but will get the job done.

njhussey
10-04-2015, 12:39 PM
Neil It is close but it works OK of course you can put washers on the cap heads to spread the load.

I will do Clive, just mounted it at the moment to check it can tension OK and that I'd got the belt length correct before dissassembling for wiring and final re-assembly.

Jonathan
10-04-2015, 12:52 PM
The Nema 23 boss is 1.5" - so 38.1mm. It's there to allow the motor to be mounted concentrically to another shaft by machining the mount to be a close fit on the 38.1mm diameter. In the case here, there is nothing to align concentric to, so all that is required is a cutout of enough to allow the boss to fit. There's often a +-0.05mm tolerance on the boss diameter, so in the past I've machined the cutouts to 38.2mm to be on the safe side. You don't want it tight else it will be harder to tension the belt. Also the cutout for the boss needn't go all the way through the material - 2mm deep would be plenty. e.g:

http://www.mycncuk.com/attachment.php?attachmentid=15122&stc=1http://www.mycncuk.com/attachment.php?attachmentid=15123&stc=1

Noplace
21-04-2015, 10:11 PM
thanks guys for all the info, one question on another topic: how do you mount the linear rails on steel boxes/frames ?
I'm thinking of designing the body out of that since its readily available locally instead of alu t-slot extrusions but I don't know the technique you use to mount them, seems you cant access under to put nuts for the bolts!

routercnc
21-04-2015, 11:34 PM
If the steel box section is 5mm thick or so then you can drill and tap it and bolt the rails directly. You can optionally place a strip of steel inside the section clamped to the underside of the top surface and drill and tap through both to get better thread engagement.
Be aware that your rails will only be as flat and planar as the top surface of the box section so read up on epoxy mounting or shimming methods to get the best DIY result.

Noplace
24-04-2015, 05:58 AM
Thanks for the great info, I would like to try epoxy but I have no experience and I'm afraid it just might be messy and don't think local workshops here have experience in doing it. would shimming be more approachable and any guides on that?

on a different topic I got my VFD (spindle still in the way) and would appreciate if you could confirm wiring:

this is a FC300-2.2KW

http://www.mycncuk.com/attachment.php?attachmentid=15196&stc=1http://www.mycncuk.com/attachment.php?attachmentid=15197&stc=1 http://www.mycncuk.com/attachment.php?attachmentid=15198&stc=1

So L and N are input obviously, PE is ground, PB P+ are braking resistor connection.

first do I connect PE to both spindle and input ground or just input ground? I'm assuming spindle comes with 4 inputs so 3 of them would be the U V W and last one is earth, is that correct?

second, I have this board called C6 http://www.cnc4pc.com/Store/osc/product_info.php?products_id=58 which is supposed to control the speed and on and off/dir from the software(mach3) once I connect it to my BOB.

would you be kind to confirm the connections between the board and the VFD? the only one I figured is analog output to AVI.

the board has separate ground for the analog and digital, should they be both connected to the COM inputs in the VFD? and there are two COMs which is confusing me further.

Boyan Silyavski
24-04-2015, 07:24 AM
Generally you will need the C41 board not the C6 for spindle control. why did you do that?

c41
Inputs a PWM and outputs an analog 0-10VDC.

C6
• Inputs a frequency (step) and outputs an analog 0-10VDC.




Read the manuals how to connect them:
http://cnc4pc.com/Tech_Docs/C6R6%20and%20Huanyang.pdf

as an answer to your question from the manual:
Make sure the grounds of the analog circuit are keep
isolated from the logic (+5vdc). Use a multimeter to confirm there is no
continuity between the two grounds before applying power.


Dont be in a rush. :toot:

Noplace
24-04-2015, 08:05 AM
I'll be using the C6 with C35 from same site, I checked with their support and they confirmed that they work together so I assume it would work and mach3 could output the required frequency(step) signal, did I miss something? please enlighten me :D

JAZZCNC
24-04-2015, 10:38 AM
I'll be using the C6 with C35 from same site, I checked with their support and they confirmed that they work together so I assume it would work and mach3 could output the required frequency(step) signal, did I miss something? please enlighten me :D


Yes they will work fine. The difference is that with a Step based spindle control you use or lose an Axis output. With PWM then you don't.



Read the manuals how to connect them:
http://cnc4pc.com/Tech_Docs/C6R6%20and%20Huanyang.pdf

This NOT a Huanyang Vfd.!! The setup is similar but the connection terminals are different names and it's not wise to presume just because they are similair labeled they actual do the same as Huanyang or any other Vfd.

Also looking at the table for VFD you provided the Analog and Digital input Logic (which is 24V not 5v) share the Same ground so maybe can't use this board.? Check with a meter to be sure but normally Analog as it's own isolated common.!

Edit: Also the Spindle 99.9% probably won't have a Ground wire. It may have 4 connections but one won't be used. Again use meter to find one that isn't which is often pin4 (look close they will have numbers)
Regards using the PE: Then take the cable shielding at the VFd end back to PE connection. Leave spindle end shield unconnected.

Some people use the 4th connection in spindle to Ground the spindle but I find it's not required if machine frame is grounded.

Boyan Silyavski
24-04-2015, 04:34 PM
Hi, it was early in the morning so did not have time to write much. Like Dean said, the board will work but you loose axis.
I have no faith of China so i do the same, check all with meter. Especially the ground.

I always use contact from the VFD on the Estop chain so all stops if motor digs in material and VFD trips or if there is a trip for any other reason.Seems Y1B and Y1C in your case, check manual further.

Noplace
29-04-2015, 05:50 AM
Here is the full manual for the VFD:
https://drive.google.com/open?id=0B8pTKp1UomcmMDkyUHBWM3BMZlhEbzJxclVsRkVIa VJXUUlV&authuser=0

if anyone has time I would appreciate you checking it.

from what I understand:

there are function pins (X1-X8) that can be programmed for multiple functions but default is shown in the diagram showing:
X1 - forwrad start
X2 - reverse start
X3 - stop

so if I can get the right way to hook into these I think it will work.

but also in the manual it states we have to change some default settings to allow controlling start/stop and frequency from outside.

but what I don't understand in general is the need for relays, maybe someone with electronics experience can explain it, isn't it possible to just hook the pins coming from BOB to the inverter input ? unless the relays give a higher voltage?

I understand how relays work (a bit lol) but was wondering how they are functioning in the C6 ( are they outputting 12v being controlled by 5v) ?


anyways thanks for reading and hope someone is bored enough to open the manual and read through! haha

JAZZCNC
29-04-2015, 09:01 AM
Ok well the need for a relay is to act as the switch.
The vfd will provide 24V source which you take to which ever input you want to use. The relay acts as a switch and keeps the digital input using the same potential as the source.
If you use an external voltage it won't be at the same potential.!!!!! . . . . Hey what the hell is the Potential he's asking him self.? :cower:

Basicly it's ground and all it means is the digital input needs to use the same ground as the source voltage. (Or often other way around and Digital input provides 24V which returns to Com ground)
Either way there must be a path back to ground for the cicuit to be made.

Relays: Well from your statement then I don't think you do fully understand how a relay works.? A relay is just a electro mechanical switch and doesn't output any voltage.
The coils of the relay are controlled by voltage you or the device controling the relay apply. The Contacts of the relay are the switches which open or close depending on type. NC or NO.

In the case of the C6 board the Coils are controlled thru the BOB using "M" commands in g-code. The contacts you just use to make or break a circuit.
IE: M3 would turn on the relay coils closing the NO contact which you run the wire from 24V source on VFD thru one side of contact and back out the other to Digital input on VFD.

Noplace
29-04-2015, 10:23 AM
thanks that's a good explanation, I had a vague idea of relays but forgot since its been a long time I read about them.

still I'm not 100% clear on it. the relay will be my switch to turn on/off connection between VFD ports. relay has 3 pins : NC/NO/VLIN
-connect 24v to VLIN ?
-connect X1 to NC ?

or

-connect COMM to VLIN
-connect X1 TO NO

or

-connect 24v,comm,X1 to NC,NO,VLIN

sorry for sounding stupid but I need to be sure and understand correctly.

Noplace
30-04-2015, 08:07 AM
Vendor sent me this to assist also, seems the frequency control is DC so not sure if I can use my board :(
http://www.mycncuk.com/attachment.php?attachmentid=15224&stc=1

Boyan Silyavski
30-04-2015, 10:29 AM
Hi,
:toot:Don't make it more complicated than it is. And RTFM:toot:. Read the manual i mean :thumsup: Ok i read it for you so:

What you need to make all work in real life and what you would actually use are exactly 6 things:

1. connect the 3 wire cable to the VFD to power it - 2 x 230v AC wires to L and N to power the VFD and connect ground wire to PE

2. connect U V W to the spindle and the shielding of the cable to the spindle ground or body.

3. connect one of your BOB relay outputs to X1 and Com. When the relay is closed by Mach3 the spindle will start

4. connect via 2 wire the 10VDC output from the C6 board to the VFD, where +10v goes to AVI and ground to COM on the VFD. Thats the spindle speed control

5. optional: split the estop wire and connect both sides to the Y1B and Y1C, so when the VFD is powered all will be ok and the continuity normally closed, if the VFD trips due to bit dig in material or whatever the contact will open and CNC will Estop.

6. program the VFD:

assuming you have bought 2.2kw water cooled spindle you must leave all default and change only the following:

P002 just check if its right for the motor you have bought, 220V default value
P003 400


these 2 are not clear to me. Normally on other inverters its the only place to say the motor accelerates and decelerates for 10 seconds. But in the manual i saw other place also. So - program them as bellow and if the motor continues to accelerate after 10sec and is not completely stopped after command for 10 seconds, then clean them both to 0
P013 10 and remember at mach3 to make for 10 seconds spindle start and stop delay at the spindle screen
P014 10


P021 400
P025 0 this when you have successfully control the start run and speed via mach3. You wont need more to touch the VFD for any reason after that

P064 1 again-you don't need to touch the VFD once all is working, all can,should and i would say: for the sake of not forgetting something - must be done via Mach3 Do yourself a favor and buy a good screen like MachStdMill (http://www.calypsoventures.com/machstdmill.html)

P065 1 same what i said above

P067 0 believe me on this, you don't need reversal . the only thing that could happen is you make a mistake and break expensive bit, have been there, done that


PS. Thats it, its not so difficult. Check again what i say for any mistakes and be happy chappy

PS2. Yes, my VFD has connected PE ground both to the ground of cable that powers the VFD and both to the spindle cable and hence the spindle ground. Difference is that i have the separate ground connections on the VFD to do that / Mitsubishi brand/ So i believe both ways is ok. Even if you don't connect Spindle ground to VFD ground it will work, but remember to properly ground the machine itself

JAZZCNC
30-04-2015, 10:44 AM
Yes it will work fine the C6 board is putting out a DC signal.

Ok well this is a different diagram which looks like the Analog com is isolated from input logic and will work. It also resembles the terminals on the actual VFD.

So in this case you are ok and the C35 board will work. Wire it like below.

15225

Noplace
30-04-2015, 10:52 AM
Man you guys are awesome! thanks a million silyavski for the details. and Jazz for the confirmed diagram!

now just waiting for the Spindle shipment to try it out!

Clive S
30-04-2015, 12:09 PM
connect U V W to the spindle When the spindle starts for the first time make sure it is rotating in the correct direction if not reverse two of the phases ie swap U and V or U and W that will reverse the direction. ..Clive

Noplace
03-07-2015, 07:45 AM
Heya everyone, I've been shy of posting any updates since last time because I'm afraid of all the judgement I will receive from you hehe. Mostly because it has been a rough half year of finding a good workshop to machine all my plans, unfortunately in my country the quality of workshops is pretty low compared to you guys. and I am no machinist so I don't have the skills nor the equipment to do it by myself. (but hopefully in the future)

So I hope whenever I post something please don't judge anything that is not square or straight or doesn't look machined well as my goal was to get this thing running and be able to cut even if not perfect the amount of knowledge and skill I have acquired from building this is a ton.
But of course any tips and constructive criticism is appreciated!

of course lots of knowledge and wisdom was gained from the posts of people in this forum. my plans was based on your comments plus other machines designs which were posted here. again its not the best but I think I'm satisfied with what I came up with.

It's not complete but almost all parts will be ready this week and I will start assembling everything.

I had a issue with shipping my spindle because china post takes forever to reach my country so the supplier shipped me another one which hopefully be received this week. ( I think the original shipment got lost, or maybe I'll receive it after a year! heh )


the first thing I did when I started is build the electronics panel so I have tested it before and got it all working, the only thing left is to test the VFD with the spindle and hopefully make it controlled via mach3 with the generous instructions from the above posters.

so for now a small update, here is a video of my x-axis one side testing with a drill. I have switched the frame from Alu T-Slots to steel square sections, it came out decent but might need adjustment :hysterical::hysterical:


https://youtu.be/zZthFVKWcD0

Clive S
03-07-2015, 08:47 AM
Well it seems to be coming along nicely don't be worried about any judgement as it is generally meant well to help you along the way.
If it was me I would drive the screws through belts with a 1:2 reduction as that might help with resonance etc. Keep up the good work. ..Clive

JAZZCNC
03-07-2015, 09:51 AM
Heya everyone, I've been shy of posting any updates since last time because I'm afraid of all the judgement I will receive from you hehe.

Don't be afraid your doing a very nice job and we have seen much much much worse.! :applouse:

Robin Hewitt
03-07-2015, 01:41 PM
I like driving through belts because it saves trying to line things up. However if you simply bolt the motor to then end of the screw and do not care how much it wobbles and twists, all you have to do is stop it turning and you can have a much better connection than you could possibly get through an expensive coupling :D

Noplace
04-07-2015, 08:52 AM
Thanks guys will consider the suggestions.

now all i have remaining to machine is the motor plates, any advise on the designs ? the motor screw holes are not in correct position so please ignore that.

http://www.mycncuk.com/attachment.php?attachmentid=15661&stc=1http://www.mycncuk.com/attachment.php?attachmentid=15662&stc=1

routercnc
04-07-2015, 08:18 PM
Looking really good, well done.

Be aware that if you turn a stepper using a drill it will generate power (like an alternator or generator). If it is connected to the stepper driver board this can be a bad idea!

For motor mounting plates you need to have slots not holes so you can tension the belt. 20mm or so slot is a good start but you'll need to decide based on the standard belt lengths available and making sure you can tension it. There are some online belt length calculators available so make sure you use those and place the centre of the slot in the nominal position.

The motor plates are usually pocketed with the motor set into the plate allowing the drive belt to run free over the top surface. You've got the motor sitting flush with the rear surface so you are having to cut all the material away in the middle to allow the belt to run. Not saying your way won't work but its usually done the other way to keep some strength in the bracket.

Noplace
05-07-2015, 05:45 AM
Looking really good, well done.

Be aware that if you turn a stepper using a drill it will generate power (like an alternator or generator). If it is connected to the stepper driver board this can be a bad idea!

For motor mounting plates you need to have slots not holes so you can tension the belt. 20mm or so slot is a good start but you'll need to decide based on the standard belt lengths available and making sure you can tension it. There are some online belt length calculators available so make sure you use those and place the centre of the slot in the nominal position.

The motor plates are usually pocketed with the motor set into the plate allowing the drive belt to run free over the top surface. You've got the motor sitting flush with the rear surface so you are having to cut all the material away in the middle to allow the belt to run. Not saying your way won't work but its usually done the other way to keep some strength in the bracket.

okay great I'll start working on that but if my plate is 20mm thick, the pocket depth would eat up the shaft length, so is it acceptable to have the pocket area maybe 10mm thick only for example?

Clive S
05-07-2015, 09:10 AM
okay great I'll start working on that but if my plate is 20mm thick, the pocket depth would eat up the shaft length, so is it acceptable to have the pocket area maybe 10mm thick only for example?Yes you only need a few mm to mount the motor. ..Clivehttp://www.mycncuk.com/attachment.php?attachmentid=15665&stc=1

njhussey
05-07-2015, 09:26 AM
As Clive says you only need 2 or 3 mm, I've got about 3mm left for my Z stepper out of the 20mm plate...there's no real force acting on it so it doesn't need to be super strong.

Noplace
05-07-2015, 09:35 AM
Thanks I think I got it now, here's one of em with 5mm thickness for motor:
http://www.mycncuk.com/attachment.php?attachmentid=15666&stc=1http://www.mycncuk.com/attachment.php?attachmentid=15667&stc=1

njhussey
05-07-2015, 09:45 AM
Spot on....

Robin Hewitt
05-07-2015, 12:30 PM
I have never found a pulley separation calculator that got it right. I draw the two PCD's at around the separation I want, add two tangents to connect them as the belt would, trim the circles to those tangents, list the two arcs and one tangent then tally their lengths. Undo until I am back at two circles, tweak the separation and start again until I get it near as makes no difference. If you mount motor and shaft bearing in the same piece of metal you don't actually need any adjustment if your machine is accurate.

Make sure none of the pulley bolts coincide with the belt and if you are really canny you add a fixing for the plastic conduit that protects the motor leads, because that is never in quite the right place if you forget it now :eagerness:

Noplace
05-07-2015, 05:17 PM
Hey guys, so just encountered an issue which is upsetting but hopefully with your guidance I can fix it. I didn't get a chance to take photos of the machine to show the problem but I'll explain it first now and hopefully post photos later if needed.

so I connected the actual side plates to the X Axis rail and ballscrews:
http://www.mycncuk.com/attachment.php?attachmentid=15668&stc=1

if you notice bottom 4 M5 screw holes are for connecting to the ballscrew nut bracket, this is the same screw you saw in the video, what happens is there is a mismatch between distance of the (4 M5 and 4 upper M8 holes) in the plate and the screw and rail distance so I have to lift the side plate a bit up to match the 4 M8 threaded holes and the when I screw everything fit the ballscrew is forced to strain upwards and causing me jittery movement if going slow along with noise and stalling at the far end side ( tested with drill just like video ) . it is opposite of result in video , very bad hopefully ill capture it but I don't want to repeat putting the sides haha.

so my question, can you just solve this by machining the side plate to have the same slot solution as we discussed for motor plate?
instead of 4 m5 holes ill have a slot of same radius but gives me little tolerance to adjust the height correctly?

hope this is clear, if not I will post a photo of the real thing but the place I have my stuff in has no Air conditioner so I have to plan a shower after it haha.

njhussey
05-07-2015, 05:28 PM
You can slot holes so that you can have adjustment there's no problem there, of course it's better if they're spot on but once they're tightened up it won't really matter. I cocked up the dimensions on my Z back plate for the lower bearing plate for the Y axis and they're slightly slotted, it's still fine!!

Clive S
05-07-2015, 06:47 PM
After you have put in the slots and you get it all true you could then drill another hole through and put some dowels in to hold it in position. ..Clive

Noplace
06-07-2015, 10:23 PM
one of the local workshops made it for me, will test and cross fingers and hopefully no more stress on ballscrews.

on a separate note, back to the spindle I have tested it and seems to be working well with the relays and mach3, the speed is not being controlled accurately and I suspect the spindle pulley setting in mach3 but still didn't figure it out, ill post a video of this issue soon.

but main thing about spindle is I ordered and received a braking resistor, its 200W 70Ohm as per the spec in the document. I know it's not needed but thought what the hell, I just have to revert the P14 setting the sylveski mentioned earlier and I think all the other default settings are good. if anyone wants to advice on this part please let me know.

thanks!

Boyan Silyavski
08-07-2015, 01:16 PM
I have never found a pulley separation calculator that got it right.


This one has it right (http://www.bbman.com/catalog/belt-length-calculator.html). Proven a couple of times. Also drawing circles with pulley external dimension / teeth/ as per specs, connecting circles with straight lines at tangential points, deleting unnecessary and using CAD to calculate total length has proven spot on, even for a couple of pulleys where small to none adjustment was necessary.

Lee Roberts
08-07-2015, 06:44 PM
Sweeeet find Boyan, I couldn't get my head around it all when trying to work this out, this point and click link is great!

.Me

Jonathan
08-07-2015, 08:05 PM
That calculator matches the sheet called "Belt Length" in mine:

http://www.mycncuk.com/threads/5848-Calculating-timing-belt-lengths

Looks like there's a slightly discrepancy on the sheet where I did it the other way round. Perhaps I should have worked out the formulas myself, not copied the nearest source...It's two circles and two lines, how hard can it be!

I think the problem here is more the tolerances on the pulleys and belts - they're not much, but enough to require a small amount of center distance adjustment to get the correct tension.

Jonathan
08-07-2015, 08:32 PM
Just had a go...

http://www.mycncuk.com/attachment.php?attachmentid=15682&stc=1

Anyone want to check it?

Boyan Silyavski
08-07-2015, 08:42 PM
Exactly. There is some small adjustment necessary as pulleys go bigger. So you should include the correct pulley formula in that calculations to begin with.

Here bellow is a screen snip from the parametric pulley i draw. The formulas are correct for any tooth count HTD 5 pulley

http://www.mycncuk.com/attachment.php?attachmentid=15683&stc=1

Jonathan
08-07-2015, 10:26 PM
Just checked, the mess I just posted correctly calculates the total perimiter for what I drew.

Silvaski - your formula there is helpful for drawing the pulley, as it includes the correction (0.57mm) for finding the difference between the pitch diameter and the actual pulley diameter. However for calculating the center distance and belt length, we only need the pitch diameter (D=N*p/pi).

Looking at the javascrip on the website you're using (http://www.product-config.net/catalog3/d/bbman/scripts/configurator_functions.js), we can see the following:


theta = Math.asin((pitchDiameterA - pitchDiameterB) / (2 * englishDesiredCD)); costheta = Math.cos(Math.asin((pitchDiameterA - pitchDiameterB) / (2 * englishDesiredCD)));
desiredBeltLength = 2 * englishDesiredCD * costheta +
Math.PI * (pitchDiameterA + pitchDiameterB) / 2 +
theta * (pitchDiameterA - pitchDiameterB);

Their expression for theta is the same as my alpha.
For the overall belt length, the 2*CD*costheta is the same as my formula for 2*L, they just used trig not Pythagoras.
The expression pi*(D+d)/2 matches my formula - they've just factorized it and used diameters not radii.
The last item, theta*(D-d), is the extra length to account for the small angle of belt that is used due to the difference in pulley diameters. Again, if you re-arrange my formula then this term falls out. You can see if pulleys are the same size, i.e. d=D, then that part of the equation is zero.

So their formula is identical to what I just derived.

Then they round to the nearest integer teeth belt size and use some crazy looking formula to back-calculate the center distance.


v = 4 * beltLength - 6.28 * (pitchDiameterA + pitchDiameterB); centerDistance = (v + Math.sqrt(v * v - 32 * (pitchDiameterA - pitchDiameterB) * (pitchDiameterA - pitchDiameterB))) / 16;

Whatever floats their boat...

Noplace
16-07-2015, 07:23 PM
What's up gang , I'm in London on holiday and just ordered a nice vice from rdgtools and some clamps for this upcoming machine , at least make use of the free shipping haha.

Anyone got suggestions on useful things to get from the country but not so heavy?

routercnc
16-07-2015, 11:28 PM
A DTI to square up the vertical face of the vice jaw to the spindle (swinging finger type rather then vertical plunge type), plus some parallels to raise work up in the vice but keep it parallel to the base of the vice.

And sorry about the rain over here, it's supposed to be summertime.

AndyGuid
17-07-2015, 03:57 AM
. . . . some parallels to raise work up in the vice but keep it parallel to the base of the vice.
.
Thanks for that routercnc, as a lay man I've often wondered about the purpose of these "parallels" that folk keep on mentioning, but hadn't yet got around to finding out. Now their purpose makes total sense, and here's a video.
.
Machining Tips: What Are Parallels Used For? https://www.youtube.com/watch?v=nlLVEXXlFnY
.
Cheers, Andy

Noplace
17-07-2015, 07:31 AM
A DTI to square up the vertical face of the vice jaw to the spindle (swinging finger type rather then vertical plunge type), plus some parallels to raise work up in the vice but keep it parallel to the base of the vice.

And sorry about the rain over here, it's supposed to be summertime.

Thanks I already got those covered before. no worries about the rain so far it hasn't bothered us and the weather overall is a step up from the humidity and heat lol. although it's quite fascinating how it alternates between cold and hot during the day and even both at the same time!
do you feel its like that or are we imaging it cause we are new to the place?

Robin Hewitt
17-07-2015, 11:15 AM
This one has it right (http://www.bbman.com/catalog/belt-length-calculator.html).

I have book marked it and I will give it a try next time I set a pair of pulleys.

It took me a while before I could bring myself to mount pulleys with absolutely no possibility of adjustment, but now I can't imagine why :lemo:

Noplace
01-08-2015, 09:20 PM
Quick question gentlemen, on my long axis I have a motor ballscrew setup for each side, what is the best way to align & make parallel both rail blocks/side plates/etc before attaching the gantry pieces and make one of the motors a slave? should I get a long machinist square? I don't have one that would reach all the way to the other side atm but would that suffice anyway?

thanks!

njhussey
01-08-2015, 10:49 PM
I bought a straight edge and set one rail straight. Then put the carriage block on the beatings and set it square with a dti mounted on the straight rail. Then set the carriage plate square on the other rails carriages. Then put my gantry bottom plate on setting it square with both carriage plates by putting the end plates on as they fastened to both the carriage plate and gantry bottom plate ends, checked with engineers squares. Then drilled and loosely fastened the other rail at one end and sliding the gantry down the rail I marked, drilled and tapped as I went down so using the gantry to align the rails....

Noplace
09-08-2015, 09:22 PM
Another question gentlmen, when I mount my motors, how do I determine the best tension on the belts? both my gantry and Z will be belt driven and I have already used a calculator site to determine the belt length ( and bought it ) based on the distance between the points. but then what actual distance would I screw the motor at?

thanks!

Noplace
25-08-2015, 09:46 PM
Update:

had issue with my Z motor turned out the cable had some issue so I just cut one side and directly connected it to the driver instead of the 4-pin plugs setup, works fine now.

assembled everything and tested and so far satisfied, still I got a long way to get it right:
things need to be done:
-Spindle speed control via mach3 : had issue before of speed being off, probably needed adjustment of the voltage or something.
-limit switches : using software limit only at the moment
-checking alignment/parallel via DTI : to be honest I have no training on using this properly and feel like my machine doesn't have room to adjust correctly, however I can live with a little bit of error for now, as long as the thing works!
-making triangular support legs with leveling: something I missed was to make the frame have adjustable height on each corner, now am thinking of just mounting extra 4 pieces on each corner of the frame and have those lift the whole thing up and balance accordingly
-Drag chain attached to frame : again my stupid and impulsive attitude prevented me from designing a side where drag chain can sit so I have to think about manually drilling and just attaching a flat panel so it can sit on it, no big deal I guess for now.
-Double check tension of belts : again no formal training so no idea how to do it properly but by feel I think I got it decent tension :hysterical:
-Connect water cooling to spindle
-Cable management of Z axis
-Actually cut something : will probably try wood(MDF) first, then maybe try my luck with other material and ultimately aluminium, anyone wanna recommend speeds and feeds for me?

-and many more I'm sure, hope I get some positive feedback from you guys in order to make it better!

A quick photo of the machine:

http://www.mycncuk.com/attachment.php?attachmentid=15949&stc=1

Video of axis movement , before mounting spindle( at time of this post it is still uploading but give me 20mins or so plz hehe)


https://www.youtube.com/watch?v=sIeMDkg2KVI

am sure u guys might have some comments, particularly on sound of long axis movement, had lots of issues with it being flexing/bending if I tighten the gantry too much or so, the ballscrew ends might need shimming but not sure how to approach it yet.

toomast
29-08-2015, 07:32 AM
Your gantry motor belt is looking extremely loose on video.
Just google or youtube - timing belt tension - and you will be expert belt tension operator.

Noplace
29-08-2015, 10:48 AM
thank you already fixed it but I will have to learn the right procedure as you mentioned.

routercnc
29-08-2015, 03:39 PM
I tighten belts by making sure I can just about twist (by hand) the bit of belt run furthest from any pulley by about 90 degrees. I know this is also subjective but it should get you somewhere close

Noplace
11-10-2015, 07:49 AM
Hey again, yesterday I was finally able to test cutting aluminum after getting the t-slot table and fixing it in the frame. I need as much guidance and advise as you could provide me since I had several issues.

I was spraying the bit with WD40 as well as having the mist coolant system spraying water and air ( but the water/oil valve was off so only air ) and I did that to get the chips to clear since I was milling a hole, however it was far from ideal and although had chips flying in direction of air still had plenty not moving out of the hole, I did a slight adjustment to direction and angle of nozzle and helped a bit but I didn't want to just keep doing that.

second issue was that the chips that flu were flying onto my long axis rail and a bit on the ballscrew which was behind it, wasnt an issue now but it will definetly be one, I held on purchasing dust covers because the supplier i found asked for a high price, appreciate if anyone can point me to low cost solution on this part

third issue is that the piece was a bit hot to touch, so I guess I failed of having the heat transferred to chips instead of the part/stock, appreciate if anyone can guide me on proper oil/water/air combo for lubricating and cooling during milling aluminium.

spindle was around 7500RPM feed rate 150mm/sec (taking it real slow to be cautious) however I read somewhere that aluminium needs a bit higher feed rate so to not stick, but not sure about that, your help here is again appreciated.

cutting tool was 4flute 8mm HSS, test was milling a circle with 23mm radius and 20mm depth, my stock was just a scrap and it needed facing on all sides like no body's business, but this was just a test and wasn't worried about it being a bit tilted and not reach all the way through ( you can figure by the photo and the small cylinder piece left at the center)

I still am not sure how parallel my spindle is to my table and how much error is there when I move it length/side wise but it seems decent enough for now as I'm way below the level of making precise parts. will definitely be asking for tips on this as well but I also know that due to quality of parts and my labor it wont go beyond a certain level of accuracy and precision.




here are some photos, am sure you will laugh when looking at the back side photo but I will try to make it tidier hehe, also am a bit sad about having to put the vise horizontally as opposed to the standard way but thats because I opted for bigger/lengthier t-slot table for mounting large wood stock as opposed to having a a smaller t-slot table but horizontal slots instead of vertical. it is bothering to turn the vise but it's a small issue no big deal.

16269162701627116272

Clive S
11-10-2015, 09:49 AM
It looks like you have done a profile cut to make the hole A pocket would have been better to have the hole cleared.
You don't say how many flutes the cutter has etc.

Noplace
11-10-2015, 09:55 AM
It looks like you have done a profile cut to make the hole A pocket would have been better to have the hole cleared.
You don't say how many flutes the cutter has etc.

Sorry updated the original post, it was a 4 flute cutter. I just used an online g-code generator to generate cutting a hole, it goes down 3mm depth at a time and makes it a circle path. I'm already using hsmexpress so I'll do the toolpath on that next time and see.

Clive S
11-10-2015, 10:50 AM
Sorry updated the original post, it was a 4 flute cutter. I just used an online g-code generator to generate cutting a hole, it goes down 3mm depth at a time and makes it a circle path. I'm already using hsmexpress so I'll do the toolpath on that next time and see.Try a two flute cutter at about 14K with a pocket tool path

JAZZCNC
11-10-2015, 12:35 PM
Hi Khalid,

Nice to see it working. 4 flute cutters are no good for aluminium because has you found out you can't remove chips fast enough so they get re-cut chips causeing cutter heating of material and tool. Your very lucky you didn't go into melt down and Gum up the cutter with those feeds/speeds.

My standard setup is to use 3 flute Carbide Ripping cutters for roughing leaving 0.35mm wall material cutting approx 40-50% Dia DOC and feed rate between 900 -1600mm/min. Spindle speed 14000-24000rpm all depending on material grade and how big a hurry I'm in.

I Finish with a Full depth pass using single flute HSS to remove the 0.35mm material. Any where between 9000-12000rpm and feedrate 600-900mm/min.

When cutting Aluminium there is NO one cutter or feedrate/DOC etc suits all and each grade of material cuts different, infact the same grade can differ from batch to batch. Lower grades also have hard and soft spots which can catch you out if cutting parameters are close to max'd out.

So for this reason you'll find your constantly tweaking with settings to suit your machine and material being used at the time.
In all cases you need at least blown air cooling to clear chips and ideally you want some form of coolant, mist, odourless mist or flood all work good.

Another tip is don't use cutters any wider than 8mm if slot cutting at any depth has the cutting forces increase hugely and stress the spindle/machine. Wide cutters are good for shallow surfacing or deep edge milling with lower step over. Just avoid deep slot milling with them.

Noplace
13-10-2015, 07:38 PM
new issue with auto tool height, any insight is highly appreciated

I’m using C35 http://cnc4pc.com/Tech_Docs/C35R1_2_user_manual.pdf to control my machine and everything works great, trying to setup auto tool height but there is a problem with the wiring. I tried wiring port 15 and ground pin as the two points for my tool height accessory and there is nothing wrong with it until I hook the thing to the tool/spindle. the issue is that my spindle is grounded to the backpanel of all electronics and that in turn goes back to the earth wire in the electrical socket. never had an issue until the auto tool height wires touch each other while also hooked to the endmill/spindle, when they touch suddenly the unit gives an error and stops working until I re connect to the PC and restart mach3.

so in short, if the C35 port 15, ground port and my ground point all connect Mach3 will pop an error that the motion controller is disconnected.
I also saw very tiny sparks when I made the plate touch the spindle and the wire with hook.

have I made a grave error by putting my VFD in the electronics enclosure which in turn made the spindle ground connect to it and in turn made my whole machine the ground point?

Noplace
08-11-2015, 11:00 AM
I guess no one cared about the previous issue since it sounds idiotic from my side :cower: haha anyway I solved the issues I verified my grounding concept is sound ( I think lol )

appreciate any input on a new issue: I got my X and Y axis setup to travel at 10m/min 1m/s^2 and they do so decently but my Z can't handle more than 7m/min .5m/s^2 , I tested the motor without any load and it was fine upto the desired speeds but not when connected back again with the belt. my question is what can I do to make it better? two reasons I can think of is the linear rails might not be aligned perfectly with the ballscrew causing it to use more force, should I open it all up and tweak? also the weight of the spindle is maybe 12KG or so (feels heavier for sure) might it be that the motor just doesn't have enough torque to move it at high acceleration?

all my motors are 3.1Nm nema23 from zappautomation btw

CharlieRam
08-11-2015, 11:32 AM
Do you have 1610 ballscrews on X and Y and 1605 on Z as per a normal setup? Because that will affect your speed on Z.

Sent from my XT1072 using Tapatalk

Noplace
08-11-2015, 11:38 AM
Do you have 1610 ballscrews on X and Y and 1605 on Z as per a normal setup? Because that will affect your speed on Z.

Sent from my XT1072 using Tapatalk

Yes I do indeed, just to clear confusion in case there is any, the steps per and speed of the motor in mach3 is all setup correctly and I was able to reach the speeds by increasing my motion controller frequency which gives me the option to. so there is no software/hardware limit that prevents me from entering a larger speed and acceleration if I wish, the problem occurs by having the motor stall after a little jogging.

but if you mean that there is an inherited limit in using a 5mm pitch screw that I can't go past for example 7m/min can you please let me know if such is the case?

CharlieRam
08-11-2015, 11:40 AM
Yes. You would have to spin the ballscrew twice as fast as a 1610 to achieve the same linear speed

Sent from my XT1072 using Tapatalk

njhussey
08-11-2015, 11:41 AM
I'm questioning why you want all that speed on your Z? I've got my Z at 7m/min and its plenty fast enough. What are you doing that needs more speed?

Ps I've got a 1605 ballscrew on mine.

Noplace
08-11-2015, 11:45 AM
no I don't need that speed at all, sorry I'm talking about the acceleration here mostly, I was just wondering how to achieve higher acceleration without stalling.

Noplace
08-11-2015, 11:46 AM
Yes. You would have to spin the ballscrew twice as fast as a 1610 to achieve the same linear speed

Sent from my XT1072 using Tapatalk

yes machine is already setup to just do that, as I mentioned speed is fine, motor stalls If I increase acceleration to higher than .5m/s^2 range

CharlieRam
08-11-2015, 11:47 AM
But because the motor is spinning faster it will have less torque than the same motors in the other axis

Sent from my XT1072 using Tapatalk

Noplace
08-11-2015, 11:52 AM
But because the motor is spinning faster it will have less torque than the same motors in the other axis

Sent from my XT1072 using Tapatalk

thanks that makes sense! but makes me sad haha

Jonathan
08-11-2015, 12:28 PM
yes machine is already setup to just do that, as I mentioned speed is fine, motor stalls If I increase acceleration to higher than .5m/s^2 range

If you take the belt off the Z-axis and give it a slight push, does it start moving down by itself due to gravity? If not then your ballscrew and or rails may not be aligned well.

To increase the acceleration capability the easiest way is to change the drive ratio. Make the pulley on the Z ballscrew larger, or the motor pulley smaller. The torque required for acceleration is proportional to the inertia reflected to the motor. This inertia scales with the drive ratio squared, so if you make the ballscrew pulley half the size, the motor will see about 1/4 of the inertia as before and the torque goes down by the same ratio. It's not quite as good as that as the larger diameter pulley will have a higher inertia, but you'll also reduce the torque required due to friction and lifting the axis (though that is already small).

Once you think the motor tuning is correct, I recommend running random g-code rapid moves for say half an hour, as that will stress the system to give confidence that the machine will not stall. I've made a spreadsheet here to do it:

http://www.mycncuk.com/threads/5843-Random-G-code-for-testing-motor-tuning

Noplace
05-02-2016, 06:02 PM
Guys quick question, filling up the steel tubes, is it worth it? can I use normal concrete for that? any disadvantages?

njhussey
05-02-2016, 06:27 PM
I think kiln dried sand (as used for block paving) is the preferred thing to fill with for resonance. That way if you put bungs in you can empty it should you wish to move the machine...

JAZZCNC
05-02-2016, 07:15 PM
Guys quick question, filling up the steel tubes, is it worth it? can I use normal concrete for that? any disadvantages?

What's in Concrete that doesn't mix well with Steel.?? . . . Neil's suggestion is spot on and yes it's worth it.

Lee Roberts
05-02-2016, 07:18 PM
Neil is correct, problem with creat is it can become brittle and brake up/crack, when that happens you end up with "lose" in your tubes and so on.

We used to call it silver sand back in my paving/block driveway days, think there is a difference between it and kiln dried, silver being a finer grade as it needs to work it's way into all the joints on the blocks.

.Me

Noplace
05-02-2016, 07:23 PM
What's in Concrete that doesn't mix well with Steel.?? . . . Neil's suggestion is spot on and yes it's worth it.

Umm are you talking about water? :p

Boyan Silyavski
05-02-2016, 08:56 PM
Umm are you talking about water? :p


When the steel is in something without oxygen there is no problem rusting. Otherwise all the bridges will fall down.



As for the cracks cement for table tops or for workshop floors, it has additives, polymers, not to change size or crack

Noplace
07-02-2016, 11:51 AM
When the steel is in something without oxygen there is no problem rusting. Otherwise all the bridges will fall down.



As for the cracks cement for table tops or for workshop floors, it has additives, polymers, not to change size or crack

I see epoxy granite is mentioned a lot also online, what do you think of it? also do you have an example of a cement product for table tops/workshop floors so that I can check locally whats available?


EDIT: also what about UHPC, I highly prefer something that would be permanent instead of grain/sand structure that's why I'm asking about these options instead. thanks!

njhussey
07-02-2016, 12:36 PM
When the steel is in something without oxygen there is no problem rusting. Otherwise all the bridges will fall down.

Yes but the steel in bridges is normally reinforcing and therefore encased in concrete so no air can get to it, if done properly that is! Here we're talking about encasing concrete with steel, there's got to be a hole in to pour the concrete (and for air to escape) and therefore there's a way for air to get in. Now if you could pour it in a vacuum......

JAZZCNC
07-02-2016, 01:56 PM
When the steel is in something without oxygen there is no problem rusting. Otherwise all the bridges will fall down.


Different ball game and the steel is coated and protected before concrete is poured. The steel is also encased in concrete not the other way around.

Neale
07-02-2016, 03:18 PM
...or the bridge is built from Cor-Ten steel which is allowed to weather and build up a rust-based patina that coats the surface and prevents further corrosion. Not many routers built of that, though!

Noplace
20-04-2016, 07:04 PM
Hi all, some updates, most of my free time these past months I spent on cosmetics, reassembling, cable management etc and putting the enclosure since I moved to a new room which is dedicated for this machine.

here is a photo of the machine and some acrylic cuts which were the first actual project which I made for a friend of mine.
1824718248

Today I tried to face an aluminum plate ( looks funny I know, all I have at the moment hehe ) which I intend on using as a fixture for metal works. this is 6000RPM and 2 flute 1/2 cutter with 1200mm/min feed , based on sound please let me know your opinion and if you have recommended settings, I tried a fly cutter before and the results werent as smooth as this endmill. does mach3 have a wizard to generate facing operation G-code, would save me time instead of manually entering G1 commands hehe while holding the camera

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


All in all I'm satisfied and feel fortunate to have learned what I needed to accomplish this, but I wish if I could go back in time and design a better machine with automatic tool changing. wish I had formal education in mechanical engineering and machining so I could achieve better accuracy in the design,machining parts and assembly. but alas I guess that could be a future project.

Boyan Silyavski
20-04-2016, 09:14 PM
Great machine!

What about that. Or second, if you don't feel like digging 9mm into aluminum but just 3mm

1825118252

PS. With a strong cooling i mean

Noplace
21-04-2016, 05:54 AM
wow that looks aggresive, never imagined I would attempt it at this high RPM! thanks I will give it a shot with the flood coolant

Noplace
21-04-2016, 07:48 AM
last year I bought this indexable cutter http://www.rdgtools.co.uk/cgi-bin/ss000001.pl?PRODREF=4272309&NOLOGIN=1
and just tried it and its giving a much better finish, downloaded HSMAdvisor trial and for this cutter its giving me low RPM for HSS and very high for Carbide, any idea how to identify if the triangle insert is Carbide or not, all it says its Tin coated, not sure what the other abbreviations are

this is a set of them from same site, for reference http://www.rdgtools.co.uk/acatalog/1-X-TPCN-11-03-PD-INSERT-FOR-ABOVE-TOOL--1-XTIP--2439083.html#SID=404


alternatively any recommendations to replace it with a carbide one in case those are not?

Neale
21-04-2016, 09:01 AM
Those are carbide inserts. Replaceable inserts like those come in different grades of carbide and with different geometry (tip radius, for example) but they are all carbide. Never seen an HSS insert, although someone somewhere probably makes them.

Boyan Silyavski
21-04-2016, 06:46 PM
They are carbide inserts right, but i think they should not be treated like a normal carbide cutter. Instead an indexable mill tool should be found in the database and edited correctly.