I am converting a BF20 to CNC and am having a problem that I cannot figure out. The problem is that when I tune the motors in Mach 3, I can run any axis individually at 200 IPM and 50 to 100 accel with no problems whatsoever. If I then just use the arrow keys to jog one axis, then start a 2nd axis going - the first axis (the one already in motion) will start stalling and will continue stalling until I release the button for it. I can get multiple axes to work simultaneously but only by moving the accel down to 100 or less which seems like a huge jump down. My hardware is all from Keling, who I asked about the issue, and he tells me it is not a problem with the drivers or steppers and that it must be something with Mach3. Here is the setup I am running :
C11 Breakout board
KL-7220 Unregulated power supply (72 volts, 20 amps)
KL34H280-45-8A (Nema 34 640 Oz stepper - 3.2 rated amps and an inductance of 8.
KL23H2100-30-4BM (2) (Nema 23 495 Oz stepper - 3 rated amps and an inductance of 7.0)
KL-8060 (3) (24 to 80 V Driver)
I am direct driving the BF20 and I have the drivers all set
to 1/8 micro stepping. The Nema 34 is set to 3.14 amps
and the Nema 23s are set to 2.57 amps. They are all
set to half-current at idle as well.
I just set the PC up for this application - it has 2 gigs of ram, an AMD 3.0 Ghz CPU, and a GA-M68M-S2P AMD motherboard. The O/S is XP and the only software I have installed is Mach3. I would think this could be a power supply (low amperage) problem but with that power supply, I don't see how. I also don't think it is binding in the ballscrews since each axis seems to run so well on its own.
Any ideas or suggestions you guys may have would be greatly appreciated.
-Kevin