[greenene]

Machine: K2cnc 2514 with .1 lead screw
Motors: Keling steppers 425 ozin 4.17 V 2.8A
Controllers: Keling 4030 max input voltage 40V max current output 3A
Mach 3 software
Power supplies: 36V 8 A for X and Y axis
36V 8A for Z axis

All axis in Mach 3 are set up for velocity of 60ipm, accel 3.5.
Resolution currently set at 4000.

No matter what microstep I use, these appear to be the maximum parameters before the motors start slipping.

Keling has suggested that I use 1/8 microstep, but it does not improve it.
Mechanicals appear to be fine: no binding, etc.

I am down to the following options:

A. 48 V power supply and larger controller
B. .2 lead screw
C. more powerful computer ( can it be that I need a higher frequency pulsing?)
C. give up

I am cutting mostly balsa, so I need more speed.
thanks in advance.

[acondit]

I would say that changing to a .2 leadscrew would pretty much double your speed. Your current limitation is probably a function of the power supply voltage, highspeed torque of your motors, and how well your current controller actually shapes the output waveforms. A 48v power supply might help some but probably not as much as changing the leadscrews.

Changing to a .2 leadscrew will decrease by a factor of 2 the rpms required to achieve a given axis speed. I am using an obsolete older generation driver (Superior Electric), 32 volt power supply and old round steppers and can get 210 ipm on my X axis with .2" pitch leadscrews running halfstep. So if you continue to be able to achieve the 500 rpm that you are now getting, it would yield 500 * 0.2 = 100 ipm.

However, I also agree with Keling that you should also use some microstepping.

With your current setup, 50 ipm requires 10tpi*50inches=500 rpm. This means that you need 4000 steps per inch times 50 inches divided by 60 seconds per minute or 3333 steps per second. Unless your computer comes from the dinosaur era it is extremely unlikely that the limitation is caused by your computer.

Bottom line is how much accuracy you need, 0.2" divided by 200 steps per rotation gives you accuracy close to 0.001" per step. Remember the microstepping really can't be counted on to increase your accuracy it is more to smooth out motion of rotation.

Alan