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Chuck key sizes poll

Your lathe chucks key sizes

  • Total voters


Ultra Member
Premium Member
I’ve called it a few things when it unexpectedly popped out with a ‘boing’. Those i won’t repeat.
Otherwise i called it the ‘brass plunger’ - but that sounds like it belongs in the corner of the bathroom.
It’s function is to ‘keep’ things in place and aligned.
So ‘alignment keeper’ if you want to try for a bit of elagance.
Simple is good, therefore i also suggest ‘keeper’.


ersatz engineer
I finally got it.... as in toilet plunger.

It has been common to call a spring loaded rod a plunger in triggers and as lock for roataion, etc. Of course, times and names change!


Ultra Member
Premium Member
Yes, but plunger is just it's action. It's function is to "keep" the bar on and aligned.

Maybe "plunge keeper"...... LOL!

Spring loaded plunger.
Spring loaded keeper.
Spring loaded plunging keeper.

I still like just plain old "keeper".