Basic Controls Setup

[Rob Berry]

Hey Folks,

Bear with me as this may a little lengthy, but the question is pretty straightforward.

I've been somewhat lurking on this forum for a little while (10 or 12 months or so) because of my general interest in DIY CNC's.

I'm currently engaged in a project for where we've come up with a slightly unconventional 3 axis design. The principle ideas are the same as any CNC machine, steppers drive ballscrew linear guides which control an axis of motion.

As such, this is essentially a prototype unit that we need to demonstrate that it works, and our budget isn't exactly large.

I'm trying to come up with a simple, low hassle controls system that is almost plug and play for our needs.

I've seen the various threads on TB6560 after I had discovered it myself looking around for a "plug and play" controller.

While the control system is important for the demonstration, it is not as important as us proving the mechanical system.

The system, is essentially desktop size, with no axis exceeding 2 feet. What I'm looking for is a bit of a crash course on what I will need. I've been surfing but I noticed alot of the controls related discussion end up going back and forth between members looking to optimize. I'm not saying that wouldn't be great, but at this point, I need something that just works, I'll optimize the system after I prove it's viability.

So, the budget, around $350 to $400 for PS, Stepper Driver (TB6560 is what I'm looking at) and 3 appropriate steppers.

Now recommendations are always welcome.

I have done some research, but the opinions of those who know, is worth more then my ideas.

The material looking to be cut would ideally be aluminum, but when we demo it will most likely be blocks of wax. The spindle weight is around 3.2lbs. so I may need to beef up my Z axis.

Anyways, I need to begin accumulating parts within the next couple weeks in order to meet our 4 month deadline and after looking around on here, my original idea for parts was obviously a little neglected in the research department.

Like I said, any help would be fantastic.

Thanks guys,

-Bob

[TOTALLYRC]

Originally Posted by Rob Berry Hey Folks, Bear with me as this may a little lengthy, but the question is pretty straightforward. I've been somewhat lurking on this forum for a little while (10 or 12 months or so) because of my general interest in DIY CNC's. I'm currently engaged in a project for where we've come up with a slightly unconventional 3 axis design. The principle ideas are the same as any CNC machine, steppers drive ballscrew linear guides which control an axis of motion. As such, this is essentially a prototype unit that we need to demonstrate that it works, and our budget isn't exactly large. I'm trying to come up with a simple, low hassle controls system that is almost plug and play for our needs. I've seen the various threads on TB6560 after I had discovered it myself looking around for a "plug and play" controller. While the control system is important for the demonstration, it is not as important as us proving the mechanical system. The system, is essentially desktop size, with no axis exceeding 2 feet. What I'm looking for is a bit of a crash course on what I will need. I've been surfing but I noticed alot of the controls related discussion end up going back and forth between members looking to optimize. I'm not saying that wouldn't be great, but at this point, I need something that just works, I'll optimize the system after I prove it's viability. So, the budget, around $350 to $400 for PS, Stepper Driver (TB6560 is what I'm looking at) and 3 appropriate steppers. Now recommendations are always welcome. I have done some research, but the opinions of those who know, is worth more then my ideas. The material looking to be cut would ideally be aluminum, but when we demo it will most likely be blocks of wax. The spindle weight is around 3.2lbs. so I may need to beef up my Z axis. Anyways, I need to begin accumulating parts within the next couple weeks in order to meet our 4 month deadline and after looking around on here, my original idea for parts was obviously a little neglected in the research department. Like I said, any help would be fantastic. Thanks guys, -Bob

Here is a nice option but I don't know about shipping to Canada.

http://www.xylotex.com/Econo3AxSpecial.htm

While it is not the fastest thing out there it works well within its design parameters.
Of course you need to decide if it will move the weights needed at the speeds needed.
At $410 for the three axis sytem it is in your ball park. I had one but is was being used out of its designed limits. very solid just slow.
If you can, use the motors that it is listed with, not the 425's, as they will be much slower. Of course if you are using fast screws, say 2 tpi then you may need the bigger motors.

A friend of mine just picked one up for a special machine design that is starting out as a desktop router. With 20 tpi screws and the small motors it moves along at about 20 tpi without stalling the motors. More testing will decide if that is sustainable without losing steps.

Mike

[Rob Berry]

Interesting...

It seems to have everything I need, but it is on the upper end of the budget (which isn't necessarily a problem). It is certainly a viable option.

The screws were running should be gear more for resolution then speed, so something in the range of 20 tpi isn't out of the question.

How slow was it exactly? If possible I would still like to have a reasonable rapid speed.

Thanks again for replying

-Bob

[ger21]

I use a Xylotex on a 30" x 45" travel router. With 1/2-8 2 start acme (4 turns/inch), I can travel from 150-175ipm, with probably better than .001 resolution.

Be aware that the Xylotex is very intolerant of any wiring mistakes. But it works pretty god for my application.

[Rob Berry]

Yeah I read they don't have any protection on their boards.

Really eh? That's more then enough speed for what I need. And that resolution is more then acceptable.

I noticed you said ACME screws. I'm assuming this was to save cost, and I am familiar with their inherent zero backlash as well.

My budget for the entire system might a move from ballscrews to ACME screws, which originally worried me because of the extra friction. Obviously this isn't a problem.

Are you using the Xylotex unit that TotallyRC mentioned?

-Bob

[ger21]

No, I bought my Xylotex about 5 years ago. I use a 24V power supply I got from Ebay for $10 (it's a really good one, though, I got a great deal) and I bought used Pac Sci 250 oz-in steppers.

I use anti backlash nuts from DumpsterCNC.

I should mention that I did have a resonance issue, and needed to make dampers to achieve the performance I'm getting.

[Rob Berry]

Originally Posted by ger21 No, I bought my Xylotex about 5 years ago. I use a 24V power supply I got from Ebay for $10 (it's a really good one, though, I got a great deal) and I bought used Pac Sci 250 oz-in steppers. I use anti backlash nuts from DumpsterCNC. I should mention that I did have a resonance issue, and needed to make dampers to achieve the performance I'm getting.

Yeah I was looking for a 24 volt power supply as well. I found a link through this website to MPJA online 24v 8.3 amp supply. I was considering using it to power the driver. When I searched for PS info, I didn't find much in terms of something specifically recommended, but I figured this unit would probably suffice.

http://www.mpja.com/prodinfo.asp?number=16855+PS

250oz, probably would have made sense with an acme screw. I was only looking at a 187oz stepper with ballscrews.

Thanks for the info though ger!

-Bob

[Rob Berry]

The more I look at the Xylotex kit the more I like it.

Here's a question though, is it compatible with the newer Mach 3 software?

EDIT: After looking at it, I can't see it NOT being compatible.

-Bob

[ger21]

It'll work fine with mach3.

[Rob Berry]

http://www.xylotex.com/3AxSysKit.htm

This looks about right...

If anyone else has or has had this kit and has anything to say about it, let me know.

Thanks

-Bob

[Rob Berry]

Originally Posted by ger21 It'll work fine with mach3.

Thanks Ger... I appreciate the help!

[Rob Berry]

There is one thing I noticed about the board, is that it doesn't have a spindle control relay like the other boards do. Unless i'm missing something?