[shreifali]

Dear all,
I have my homemade cnc router machine based on hobbycnc pro board.
The machine was working perfectly and with a high precision, X and Y axis have the same setting (steps per unit, velocity and acceleratio,..).
No scale is set.
Till the problem arised: the y axis is behaving in a misterious way. Sometimes and frequently and when moving normally , it suddenly accelerates then back to normal speed. In addition , it sometimes travels the asked Distance and other times and unexpectedly travels twice the asked distance exactly.
Please may you know what might be the cause? Is it a defect in the driver or in the stepper motor? Or .....?
By the way i use mach3 for control
Best regards and thx in advance

[shreifali]

Problem solved: it was caused by a tiny corrosion at the back of the y axis settings jumpers causing it to be in full step although the jumper is set to be half step.
Brushed with a teeth brush and a little alcohol and the problem is gone.