[myhäje]

Is the live center's bearings defective if it has dial runout under load? What can be considered "acceptable" runout? Our shafts are somewhat oval and this seems to be the culprit.

Thank you.

[RCaffin]

I cannot see how you would get an oval shaft from a defective live centre bearing.
Unless the whole system is so loose that you are getting some (un)lucky sort of resonance?

Cheers
Roger

[myhäje]

I cannot see how you would get an oval shaft from a defective live centre bearing.
Unless the whole system is so loose that you are getting some (un)lucky sort of resonance?

Cheers
Roger

Thanks for the reply. They are oval only at the tailstock's end. About 1/8 of the length.

[RCaffin]

They are oval only at the tailstock's end.

Getting an oval finish off a tailstock????
There's something else going on here!
I got a spiral finish on some tubing once, and that was definitely resonance.

Cheers
Roger