I bought a little ER-32 collet chuck for my Jet Mini.
I use it to turn pens, yo-yo's, etc...
It's nice because unlike a jacobs chuck, it won't come loose.
I can take the pen mandrel and adjust it to any length.
It screws on to the head stock instead of just sticking into the morse taper.
This means you can use it unsupported for doing small work where you can use some thing like a bolt as a mandrel going into the piece.
I think it would probably work great for knobs...
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