[RKnack]

I am working on converting my Sieg X2 mini-mill (Harbor Freight 44991) using he FigNoggle blueprints. I have three Wantai 57bygh633 270 oz.-in stepper motors, and a Sunwin USB 4-axis controller Amazon.com: Sunwin 4 Axis Nema23 3.0A Stepper Motor USB Driver Board, TB6560 USB CNC-DIY Controller: Computers & Accessories. I have several questions:

1) The default DIP settings are for full-step. The software asks for steps per unit (I'm using inches). The motors are 1.8 degrees per step, or 200 steps per revolution. If I set it for 1/16 microstepping, do I need to figure 16 times the number of steps per revolution in my calculations?

2) Never had to calculate belt drives or gear reduction before. The z axis will be a ball-screw with a .200 lead. The drive pulley for the toothed belt will be a 14 tooth, and the driven pulley on the ball screw will be a 16 tooth. On the Y-axis, it will be the stock .0625 per revolution Acme screw. The drive pulley will be a 15 tooth, and the driven pulley will be a 30 tooth. The X-axis will be directly driven via a zero-backlash coupling, so no math problems there. How do I figure the steps per inch on the Y and Z, though? I know it seems like a dumb question, but math was never one of my strong points...

3) I have the option of wiring the motors for "high torque" (full coil) or "high speed" (half coil). Which would be the better choice given my setup?

4) Exactly what is "decay", and how do I set it? Is it one of those trial-and-error things?

5) Should I set the current for the full 3 amps, since that is what my motors call for? Or should I set it for less than that? My power supply is a 24 volt, 15 amp unit.

[RKnack]

Anybody? Nobody?

[ger21]

1) yes, but try 1/8 instead of 1/16.

2)

Z = 16/14*200*5 for full step
Y=30/15*200*16
X = 200* screw pitch

3) Since you're only using 24V, I'd probably say whichever has lower inductance.

4) not sure

5) yes, 3 amps

[RKnack]

Thanks, Gerry. I am hoping to test out my board and motors some time this weekend (too busy working during the week to do it). I at least had a chance to check my PSU when I got it - some times they're set for higher than the "advertised" voltage and can fry boards from what I have heard. This one checked out at 24v on the dot, no adjustments necessary.