The resulting hole is smaller (0.010+) at
the tailstock end. I've read about boring bar "springing" and have been
careful to try to avoid this.
The springing is going to have a lot to do with the boring bar length vs diameter (or cross section if its not round). How deep is the hole you are boring, how long is the boring bar, and what size is it ?
Also you are not using the compound screw to advance the boring bar into the work are you ? Unless you've set the compound angle using an indicator its most likely not set to be parallel to the spindle. If its not parallel to the spindle then you are boring a taper using whatever angle the compound is set at.
Regards,
Kevin Jones
Louisville, KY
