Hi, it's been a while since I was here, but like a bad penny I keep turning up.
I had a problem with my Spindle on the lathe which turned out to be a faulty servo controller, so for the time being I have gone back to my VFD and 3 phase motor setup. This issue occurs regardless of the spindle running or not, also I'm using an ESS, so I doubt it's caused by interference from the VFD.
After getting the spindle working, I thought I'd give things a try and attempted to bore a 40mm wide x 25mm deep hole in a tube. The Z axis, however was unwilling to co-operate.
The problem when I run the job is as follows:
The X axis moves to the commanded position
The Z axis remains stationary, but the DROs on the computer count down as if it is moving.
Upon reaching the commanded depth (25mm) on the Z axis (but not actually moving Z) it moves back 25 mm and this time it actually moves Z, so it is actually 25mm away from the job on the Z axis.
This repeats, as it thinks it is doing cuts, so the Z axis is further and further away by 25mm a time from the job.
I am using step and direction to control the Z axis servo driver, so to test things, I commanded G0z0 when the Z axis was at 25mm. The z moved as expected. I then commanded G1f100z0 from 25mm and got no z movement, although the Z DRO showed the axis moving to 0.
I'm a bit perplexed by this behaviour and I'm hoping someone will have something for me to try.
Cheers and stay well
Dave