Y axis is making X axis stall...!!

[fasteddy]

Hi again..

Bit more info on the problem.. It only seems to happen when moving x and y in full rapid, if one or other of the axis is not moving at full speed it does not happen i.e. it happens when rapid at 45 degrees, but not 30 degrees... If that makes sense... Sorta guessing both motors are at full throttle when moving at 45 degrees rapid..

Some more info on my setup..
X axis is a pair of SY855TH80-5504B steppers driven by a pair of PM752 drivers.. The settings on each driver is;
3200 microsteps
5.5amps

Y axis (and z) is a 3Nm nema 23 (from Zapp) on a PM540 driver, settings are;
3200 microsteps
2.5 amps

Got my specs wrong on my PSU's earlier, should be;
X axis run by a single PSU (separate outputs) which delivers 65v 8amps..
y and z share a 24v 4amp PSU..

Will test voltages tomorrow when I can get a new battery for my multimeter...
Am 99.9% sure it is something electronic as I have torn apart and rebuilt every mechanical part and everything is freely moving.. Also, I am a decent engineer and a crap electrician with only slightly more knowledge of electronics than my cat...

Steve..