I am planning on building my first machine, with the goal of being able to mill PC-Boards, to get more professional results than the old etching method. I am planning on using an Arduino as my microcontroller, and build my own unipolar stepper controller with the ULN2004 transistor array chip as my base. The steppers I want to use are from Applied Motion, 60 in/oz, 200 s/rev, 2.3V, 2.3A, and the part number is 44A501711.

That all being said, I have a few questions:
1. I am pretty well versed in Arduino code, and they provide a schematic for building the stepper controller with the ULN2004 chip; are there any sources for a prebuilt kit using that chip, or has anyone already done this and can provide feedback about using that method?

2. The motors I list, are they appropriate for this? Is 60oz/in enough torque for running a dremel head to cut PCBoards? FYI I have no problems with the power supply requirements; I have a TON of power supplies from various past projects, so i'm not concerned about supplying anything up as high as 48v @15 amps, if there is a better motor at a good price for this application. I'd like to stick to Unipolar motors unless convinced otherwise, because the controller is so much simpler for me to build.

Thanks in advance!!


EDIT: I've quickly learned that the ULN2004 will not work, as it maxes out at about 650mA!! Far below the 3A requirements of the proposed motors. I'm researching the SLA7026M chip now, as it supports 3A continuous / 5A peak. Would appreciate feedback on that chip and/or similar/better chips. Thanks!