quick question
 

A headstock live center or tailstock rovolving center which is running out when a shaft is turned all at once won't affect the shaft itself. Therefore the shaft will still be straight and concentric when complete. Am I right about this?? I have checked it several times and it looks like center runout doesn't affect the shaft if it is turned all at once. Thanks
Brian

It shouldn't until you remove the part and try to turn it again then it may be off...Bob