HobbyCNC 3 axis board build and review

[Jay C]

Yes another one. When I was looking I could only find Paul's and he was just starting so the more the merrier.

I was waffling between the three boards and going DIY. I love electronics (I should as a EE) and building my own stuff. As I read more and more about these drivers I realized it was very close to some robotics projects I did back in college. Namely PWM H-bridge driver chips from Allegromicro. Long storey short, it was cheaper to buy a kit that order all the individual parts. So now it was down to HobbyCNC or Xylotex.

I went with HobbyCNC based on threads I read on eZone, here, and other threads. It would have been easier if I could have browsed the support forum first, and been able to guage the support after the sale, which by my account is superb. Dave answers every question with a straight forward, no-BS response. I like that.

Ok, I ordered my board and a stepper motor on Sunday and it arrived Wednesday. I recieved two emails from HobbyCNC, one saying it would go out on Sunday, and another telling me it shipped. When it got here, my wife "hid" it from me as we had errands to run and she knew I'd want to jump into building it. I started at 10:45PM but had read the instruction sheets prior to that while babysitting my boy.

First thing I did was seperate the parts into piles of same parts. Then step by step I stuffed and soldered the components as instructed. All you have to do is pay attention to the silkscreen numbers and stuff the very well documented part where it belongs. I have designed PCB's so the numbering and layout are very familar to me. I took my time because there was no rush and if you don't you make mistakes

The only issue I have is that I'm missing a resistor for the 5-volt regulator circuit for the logic. I wasn't thinking of all my options, except I did go through my personal inventory of resistors to find it, and I fired an email to Dave for a replacement. I went to bed, but Dave must be a night owl as I had an email the next morning at 4AM! Does he ever sleep! I plan to go by the local Shack to see if they have the one I need, but just to let you know Dave is sending a replacement anyway.

Stay tuned for the rest of the build and some tips. One comment I have about my order is the 80oz-in stepper I bought too. The thing is much bigger than I had imagined. Thank goodness I only ordered 80oz-in, the 200oz-in must be huge. I'll use this one to power the lead screw I'm adding to my lathe (Taig) and a smaller surplus one I already have for the cross slide (and mabe the milling attachment).

Jay

[Jay C]

Update: 2/16/2005

Okay, Dave sent me the replacement 750 ohm resistor (I could have used two 1.5K ohm resistors in parallel but not really in a rush since I'm working on the mechanics of my lead screw) I need and it arrived yesterday. I installed it and tried the 5V test using a 12V field battery (for you non RC types it's just a 12V gel cell you haul out to start your aircraft engine). 6.55V ... what ... no way I was so careful and this part of the circuit on has three parts ... WTF. So I walk back through the instructions step by step and there is is in caps:

From memory so it's paraphrased "Insert the LM317 next with the tab oriented towards R12" ... DOH! Looks like I got cocky at the end and stuffed the two voltage regulators facing the same way . So I dug out my old solder sucker since my fancy desolder station was on loan to a buddy. I resolder it the right way, plug it up and get 4.99V.

So now I need to decide if I believe the superstition of "spinning the motors" or not. NOT! I assumed I already had the proper parallel cable so I didn't get Dave's kit ... $15 later I have a 10' cable en route.

My plan is to use old an AT PC P/S to drive my motors. Since I'll be turned aluminum (mostly) I don't need/cant use a lot of speed.

Note: If anyone is intrested in me assembling/testing their board/kit send me a PM ... I had forgotten how much I enjoy soldering.

Jay

[joecnc2006]

I should recieve the board in a couple of days, I hope i can put it together, I have not done any boards before. but i will try.

[Jay C]

Joe, it's straight forward and Dave spells everything out. If in doubt, just ask here or on the yahoo support list. Have you ever soldered before? if not, you may want to practice, read a tutorial, and ask questions. If so, then just make sure your tip is well tinned, watch for solder bridges (happens more with too wide of a tip), and clean your joints afterwards to prevent corrosion from the excess flux.

Have fun,
Jay

[HobbyCNC]

Originally Posted by Jay C Joe, it's straight forward and Dave spells everything out. If in doubt, just ask here or on the yahoo support list. Have you ever soldered before? if not, you may want to practice, read a tutorial, and ask questions. If so, then just make sure your tip is well tinned, watch for solder bridges (happens more with too wide of a tip), and clean your joints afterwards to prevent corrosion from the excess flux. Have fun, Jay

We have soldering tutorial link on our Yahoo hosted support group in the "links" area. Who da thunk?

Dave Rigotti

[joecnc2006]

Originally Posted by hobbycnc We have soldering tutorial link on our Yahoo hosted support group in the "links" area. Who da thunk? Dave Rigotti

I applied for the yahoo group about a week ago and have not recieved an email or anything, so not a member yet i guess.

[HobbyCNC]

Originally Posted by joe2000che I applied for the yahoo group about a week ago and have not recieved an email or anything, so not a member yet i guess.

You must follow the instructions as described on our homepage. IF you did not include the information requested, you will be denied. We get 10-20 requests a DAY from non customers.

Dave Rigotti
HobbyCNC.com

[joecnc2006]

ok thanks, i will do it not and see if i can get it going. i also sent a money order for a board to ypou monday.. look forward to checking it out and excited to get my machine a moving...

Thanks again.

[joecnc2006]

will this work 24v power supply for the HobbyCNC 3 axis board?

http://www.altex.com/product_info.ph...roducts_id=948

Thanks, Joe

[HobbyCNC]

Originally Posted by joe2000che will this work 24v power supply for the HobbyCNC 3 axis board? http://www.altex.com/product_info.ph...roducts_id=948 Thanks, Joe

Not even close! You'll need a power supply up to 44VDC that will have enough AMPS to provide at least 70% of the total stepper current draw. 10AMPS is usually enough. Maybe a "package" would have been a better choice as we supply all the materials except for the case and a transformer which we provide links to.

Dave Rigotti

[joecnc2006]

yes you are right dave, i should have gotten the kit from you... i will look again at the HobbyCNC site. thanks again you are certainly have good tech support with your site.

[HobbyCNC]

Originally Posted by joe2000che yes you are right dave, i should have gotten the kit from you... i will look again at the HobbyCNC site. thanks again you are certainly have good tech support with your site.

Email us offline and we'll work something out for you

Dave Rigotti