[joprinz]

Hi... I am new to this Board...but I have to say this is a wonderful place to find ANYTHING related to CNC... :cheers:
I am from India and most of the off-the-shelf drives as well as Drive Kits mentioned in most of the posts are from the US...but for a Hobby CNC Enthusiast like me it becomes hard to get them imported and go through customs procedures due to them being classified as an Electronic Equipment and the conversion rates along with the duties make it many times costlier than how much it would cost if it was to be made on your own. Can you guys help me out with complete circuit diagram and component list for a 3 Axis chopper drive for Nema 23 steppers ( 1.5- 2 Amp would be sufficient). I would like to interphase it to the computer using the Parallel Port. So it would be great if you could provide me the interphase circuit diagram too.
Hope you guys can help me out.
Thank You

[ger21]

www.pminmo.com

[NC Cams]

Take a look at/through the TI/Unitrode web site.

They have a lot of stepper and servo drive IC's. They also have some circuit diagrams for the high current amplifiers needed to interface the servo/stepper encoder/driver IC's to the motors (servo) and/or the motor phase coils (stepper).

I don't know of any full blown "kit" plans to go from the bare parallel port to the motor - this does require some full blown integration of the soft and hardware.

A good place to shop/check would be the Mach users group. Surely, some of the users have crafted up exactly what you're trying to do - join, post an inquiry and wait for a reply. You'll either get a kit or link to someone/someplace who's done what you're trying to do.

[rmsimoes]

if look for a3977 ic you will find lots of info at this web site and also at pminmo.com
look for open source projects.
if you look for something easy to solder, TA8435 from Toshiba it's an alternative.
can find a small board design at http://www.ottop.republika.pl/sterownik8435.shtml
it's the same ic used by Nanotec-(IMT901)
all drives need power supply, and mainly STEP and DIR info.
it all depends on how easy to find components at your place.

[joprinz]

Thanks guys. Those websites were really useful... I was wondering what kind of stepper motor is best for CNC Engraver. Unipolar or Bipolar?

[rmsimoes]

if your stepper has 4 wires it is for bipolar. if has 8 wires you can use it both ways. it is described pros and cons at one of those links.
I prefer bipolar only because it's easier to choose cables and connectors. even if buying xlr connectors and shielded cable with 4 wires from Igus the diameter is not big.
you will find there are other things to consider like torque an so on.

[workfine]

some help about TA8435 driver ,you translat it italian document

http://www.sigala.it/sergio/robotica...-24jul2001.pdf

[rmsimoes]

if you want to use ta8435, you will find schematic and pcb drawing at
http://www.ottop.republika.pl/sterownik8435.shtml
you only have to download it at
http://www.ottop.republika.pl/download/imt901.zip
need to install Eagle to use it. it's free.
to make it work connect your stepper then apply at least 24V. and logic 5V. next connect ENABLE to ground to turn on the drive, and see your stepper spinning.
and don't forget to use a good heatsink.
I have found another link with board design where you can put a 7805 ic, and you only need acrobat reader.
http://www.piter.mily.pl/index.php?i=1
http://www.piter.mily.pl/index.php?i=2
but didn't test it.
it seems easy to build and is an ic used by Nanotec.

[iroshan]

Your site is great

[q-bert]

if you want to use ta8435, you will find schematic and pcb drawing at
http://www.ottop.republika.pl/sterownik8435.shtml
you only have to download it at
http://www.ottop.republika.pl/download/imt901.zip
need to install Eagle to use it. it's free.
to make it work connect your stepper then apply at least 24V. and logic 5V. next connect ENABLE to ground to turn on the drive, and see your stepper spinning.
and don't forget to use a good heatsink.
I have found another link with board design where you can put a 7805 ic, and you only need acrobat reader.
http://www.piter.mily.pl/index.php?i=1
http://www.piter.mily.pl/index.php?i=2
but didn't test it.
it seems easy to build and is an ic used by Nanotec.

Piter link doesn't work.

[rmsimoes]

I have seen already that link was removed, but I can supply schematic and pcb design if you want to test it.

any way, I prefer that I am using at the image from http://www.ottop.republika.pl/sterownik8435.shtml:

with 5 minutes using heat transfer method I have done a really good job.

for the price it seems to me a nice solution. the last one I have done was with small fan attached to heat-sink to cool it down.

[q-bert]

Hi, this pcb looks a new version, doesn't it?

Have you included the 5V voltage regulator (7805?)? Nice!

I found a very similar circuit (here).

Pls, 1 question about C1. The 2 circuits differ mailnly for C1 value. 1000mF instead of 2200-4700mF. What is better? TY

[rmsimoes]

about the capacitor, I have used 1000uf because I have seen it at IMT-901 datasheet. I am using 3 boards with a power supply that is using 22.000uf, so 1000uf seems enough.
I have bought a few boards at ebay from http://stores.ebay.de/Markus-Mechatronics and it is using only 470uF.
about 7805 regulator, one is enough for 3 boards so I saved some money for summer vacations. with 3 drives it stays cool so don't worry. only try to use at least 2w resistors for sense resistors. 0.47 or 0.68ohms would be fine.
3 drives I have done produced more than 100 small engraved plates. so good luck.

[q-bert]

Thank you for replays, I'm going to give it a try... and have good time for your vacation!