[Trevix]

Hi all. Just enrolled...
I looked around but could not find any post about a Proxxon BFW 40 CNC conversion (you're already laughin...right?).
I've been having this little mill for a while and since I found 4 stepper (Nema 23 1.8degree 200steps per revolution 116oz bipolar), I tough I could give it a try and have some fun on this project.

I'm sure I can arrange the motor set up but I'm really concerned about the price for the driver (a gecko g540 would cost more then the mill...).
I've seen several cheap driver on sale on eBay but I would not know how to choose the right one.
Any suggestions ? How about the Power supply ?
Thanks to all

[Jeff Davis]

I would go with a controller like the Xylotex for a little one like that. I used that controller on a little X1 and have had no problems with it in about 5 years.

hth

Jeff

[Trevix]

Thanks for answering.
The Xylotex costs $410.00 and comes with motor. It would not be a saving.
I believe that a system should be made of cost comparable items (like on audio, you would not spend $100 on speakers and $1000 on amplifier...).
As I said, on eBay there are tons of driver for around $60.00. Is there any good ? What should I look for ?

[hoss2006]

Several Proxxon CNC conversions I've seen only need to use Nema 17 motors so a powerful driver is not needed.
Kdntool only use 83 oz/in N17 on their Proxxon MF70 kit which looks like a bigger mill.
Hobby CNC make a small DIY kit with motors for only $235 or you can just get the driver kit for $64.
They have 4 axis boards too.
Hoss

[Jeff Davis]

Unless Jeff change his parts lists you used to be able to buy the controller for
about $90. I recommended that based on the size motors you said you had.
The other one listed by Hoss is also a good choice for your size motors, but I think that one can only drive unipolar and I dont know which connection type
your motors are.

Jeff

[Trevix]

I made a mistake about the motors I own: they are unipolar. See the pictures:
Beside what is written on the label, as I said, I know they are Nema 23 1.8degree 200steps per revolution 116oz, 8 wires.



I am trying to pinpoint the electronic I need, but being my first with stepper motors, bare with me.

- The HobbyCNC PRO Driver Board Packages looks fine and a project that I can handle.
1) I'm not sure witich package to choose, based on the voltage of my motors
2) $250 + transformer is not really chip.

- Xylotex sells with motors and he does not ship to Europe (?) so this is out of the way.

- I've read that the G540 Gecko is a sure winner and probably a good buy for future upgrade but, looking at the manual, I've got rather confused. I am afraid of being stuck with a $299 thing that may require different motors and may be too difficult for me to hook up and hadle.
3) is it too much for my project ?

4) On eBay I found a Keling driver for $139 (1 pcs 6 axis breakout board, Built in Optical-Coupler. Surface-Mount + 3 pcs Bipolar Stepper Motor Driver, 40V, 3.0 A). Sounds like a bargain but will it fit ?
http://cgi.ebay.it/Three-Axis-CNC-Ro...item3a4eec6286

5) What about this Allen-Bradley driver?
http://cgi.ebay.it/3-AXIS-CNC-ROUTER...item4ceb9d2529


My god. There are so many at affordable prices. What whould I look for in term of specification that will fit with my motors?

Thanks for any help

[Jeff Davis]

Go with the hobby cnc board. Matches your motors well, and since this is your
first jump into CNC you probably should stick with new gear that is well documented, it will save you a lot of time in the trouble shooting stage of the
build.

The power supply you could ebay or build yourself without to much pain, the case could be about anything. If i remember right the Hobby CNC board sells for about $80 for 3 axis.

hth,

Jeff

[Trevix]

Thanks, I will do that.
Should I get the
3 Axis w/(3) 130oz-in 2.6V 2.1A
or the
3 Axis w/(3) 205oz-in 3V 3A ?

Thanks for the help.

[Jeff Davis]

Either would work fine, or you can just buy the Controller and use your motors your already have.

Jeff

[Trevix]

I'm bakc to step 1, since HobbyCNC does not sell the kit without motors.
So I will have to buy the driver only. I just hope I can find a suitable power supply...

[hoss2006]

Keling is still sold out of their cheaper 36v PS.
Circuit Specialist have several to choose from, a 30V and a 24V.
Hoss

[Trevix]

Sorry, are you saying that the Circuit Specialist 30V or 24V are a good choice to be used with the HobbyCNC driver and my motors ?
Wich one should I order ? 30V or 24V.

After several days on the web I still can not tell how am I supposed to size the power supply, related to controller and motors....

Thanks for any help

[Jeff Davis]

It seems I have confused you, sorry.
-----------------------------------
Purchase the stepper motor driver "Kit" from these guys. http://www.hobbycnc.com/products/hob...er-board-kits/ $79.00

It is in Kit form so you will need to solder it yourself or have someone do it for you.

-----------------------------------

Buy this power supply
KL-320-36 36V/8.8 or 9.6A
110V/220V $59.95

from http://www.kelinginc.net

-----------------------------------

The above 2 items and your motors is most of a CNC conversion. Along with that you will need shaft couplers, nema sized motor adapter plates, limit switches, software, 25 pin straight threw printer cable, ect.

The reference to Ebay was to keep you from buying used gear that may or may not work.

hth

Jeff

[hoss2006]

Sorry, are you saying that the Circuit Specialist 30V or 24V are a good choice to be used with the HobbyCNC driver and my motors ?
Wich one should I order ? 30V or 24V.

After several days on the web I still can not tell how am I supposed to size the power supply, related to controller and motors....

Thanks for any help

The specs for their boards recommend 24V minimum and 36V max for the EZ board and 42V for the PRO board.
The more voltage, the faster you'll be able to run.
Hoss

[Trevix]

Since my last post, I bought a 4 axis controller from HobbyCNC and a KL-320-36 36V/8.8 or 9.6A power supply from Keling.

I am bad at theory but good at practice. I pretty easily assembled the board, but I noticed that there was not schematic (I think I read somewere that Dave does this to keep its business and avoid "replicants"...even tough any electronic kit I ever bought had schematics. Bah...).
The problem was that there was not even a general wiring drawing (you know...fuse, switch, Fan, etc.).

Looking at HobbyCNC web site I learned that I could find more info only in a Yahoo closed group. I needed some kind of permission from Dave (I think) and so for this weekend I am stuck!

On CMC zone I found a VERY,VERY long thread from a guy named Diarmaid (1.257 !! posts at http://www.cnczone.com/forums/showthread.php?t=25504) who had lots of problems (he was also very inexperienced) so I though I needed more info before trying out my motors.

--------------------------------------------------------

As I said before, I have 4 Powermax 1.8 model P21NSXC.LSS-NS-03. Problem is that the vendor instruction (see attachment) said they were Hybrid (?) steppers (unless since my motors are labeled "Powermax" and the doc is labeled "Powermax II" makes the difference) and that they can be connect with 8 lead, 6 lead 4 lead (bipolar so I think this last is excluded...).
I do not have a leaded connector (so no color coding). I both a strip that, cut in pieces of 8, will allow me to wire the motors.
The color hookups on HobbyCNC docs does not help me (my motor is not listed)

Man....I have a lot of questions but may be someone can help me out with these:

1. I believe I should connect as 8 lead, right? But since on the board the 2 "COM" are connected, I have 5 wire...
   
2. The motor pins are labeled 1 trough 8. Does it matter if you start from 1 or from 8 since they are simmetrical?
   
3. How do I wire the B,b,COM,COM,a,A output from the HobbyCNC controller to the 8 motor pins ?; something like A on 1,a on 6 ,COM on 2,5,4 and 7, B on 3, b on 8. If this is not correct, will I burn something ?
   
4. Once the stepper are wired, can I safely test them (after having done the Current adjustment), using the powersupply, Mach3 on WindowsXP, without fuses (just to see if they are turning) ? (I know...do not detach anything for a while after use...)
   
5. Since the power supply has short circuit/overload(overvoltage/over temp protection, do i rellay nee a fuse (so old fashioned...)?
   
6. The power supply has its fan. The controller will have its aluminum dissipator. Do I really need another fan on the box that will hold them all ?

I would appreciate any help. I know that I will not wait ...until monday, to see the motors spinning. May be you would like to avoid farther air pollution (smoke...) from another inexperienced guy.

Buy the way...with the help of a mechanical experienced friend of mine, I have already prepared the X and Y axis for my Proxxon BFW 40. Wanna see it ?

Trevix

[Trevix]

The photo did not come out...
Let me try again

[hoss2006]

You can double check the pins on the motor to determine the coils with an ohmmeter.
I'd imagine they number 1-8 left to right so you should get a reading on the ohmmeter by
connecting pins 1&5 , 2&6 , 3&7 , 4&8
should get opens when connecting any other pin combinations.
If this the case, then
1 = A
2&5 = COM
6 = a
3 = B
4&7 = COM
8 = b

that's how I'd try it.
Hoss

[Trevix]

I tried out and it works. Thanks.
But...just to know...since on the hobbyCNC the two COM pin of each axis are connected. this is really a 5 lead wiring, isn't it ?
1=A
6=a
3=B
8=b
2,5,4,7= COM

So I'm going to use a 6 lead shielded cable with pin 2,5,4,7 of the motor connected together. To avoid ground loop, the shiel is connected on one side only. See the attachment...
Is this correct ?
Connessioni motori.pdf