Recently purchased a '95 E25J. Never worked on a swiss lathe before but have experience with the old 6 spindle cam driven screw machines and couple decades of experience operating / programming CNC mill and lathes. Anyways i have a question about using the sub spindle while parting off. Tell me if this will cause damage to the sub sub spindle drive or not. Here is what i am doing -
Machine part using main spindle.
Stop main and sub spindles.
Advance sub spindle and clamp on part.
Start main spindle.
Partoff.
Retract sub spindle.
More machining etc etc.
I am curious if running only the main spindle motor while the part is clamped with the sub spindle will build up current in the sub spindle drive and cause damage. Is it considered normal practice with these machines to run both spindles while parting off? In my mind running both motors would only be possible if they were matched at exactly the same RPM. Not close to the same RPM but exactly.