Got a long overdue mini-lathe on Friday. Checked runout using the
supplied 3-jaw self-centering chuck and got some very disappointing
readings until after fiddling discovered that one particular pinion
when tightened resulted in runout typically 1/4 of that when tightened
any other way. Even though results were now acceptable and repeatable
I still though something was wrong with the chuck based on
conventional wisdom which dictated tightening all pinions in turn.
About to mark this pinion when I discover that it's already marked.
Searching Google on >lathe chuck runout< led to the term "master
pinion" and an explanation but searching Google on >"master pinion"<
returns only 4 relevant hits. Is there another name for this pinion?
Is it common knowledge that there are 3-jaw chucks that operate this
way? Can't find any mention of this on or in the
manual that came with the lathe.
17 years ago