Re: Slow speeds with Longs motor kit
ger21 is generally a very knowledgeable guy and I would trust his advice... I would recommend trying things in this order:
1. Change the lead screw first. That may be enough.
2. Upgrade the power supply and drivers and keep the motors just to see if you can't get those motors to move. The main thing is to raise the drive voltage. More voltage = more speed. A couple of gecko-drives at 80 volts may just do it. Use one driver per motor, and feed them both from the same step pulse. Don't try using one driver for both motors (not sure if you were doing that)
3. THEN upgrade the motors.
In the end, it's no loss because you probably had to do all that anyway.
James hosts the single best wiki page about steppers for CNC hobbyists on the net:
http://www.piclist.com/techref/io/steppers.htm Disagree? Tell him what's missing! ,o)