Knowledge You Can Build On — Est. 1998
faceplate vs. 4 jaw chuck
ken chase
>In the short time I've been turning I came to the conclusion for hollowform work or deep bowls the 4 jaw chuck just doesn't cut it. I bought a good and expensive one (Vicmark) but my piece shimmies loose. The faceplate doesn't. Am I missing something? Am I wrong? Please straighten me out. I just lost a really nice piece I spent a lot of time preparing to hollow.
Thanks
Re: faceplate vs. 4 jaw chuck
John Lucas
>Ken
Without a doubt a faceplate is the most secure. Most of us use chucks to speed things up. One trick I use is to tighten the chuck every few minutes. Sometimes this will cause the piece to go out of true but the vast majority of the time this works quite well. John
Re: faceplate vs. 4 jaw chuck
jeff jilg
>I agree with John's tip. In addition you can use a steady rest to help the piece stay where you want it. This is a critical step for longer hollow forms.
Big serrated jaws...
Peter Teubel
>I rarely use a faceplate. The Stronghold with #3 serrated jaws holding a 4 or 5" tenon hold well enough for me. Of course, I really torque the chuck tight...and check it frequently.
Re: Might be jaw shape, or torque problem
Al Crandall --NE of Indy--
>I had occasion yesterday to turn on a piece in a Vicmarc chuck which had been started by another person. He had been hollowing on it for about 10 minutes when I started and the first thing I did was ask him if he had the piece firmly tighted in the chuck. His answer, as I searched for and found the chuck wrench, was "Yes". I turned the chuck key another 3/4 of a turn before it was as tight as I thought it should be. Obviously his idea versus my idea of tight are two different things. I don't normally notice my Stronghold or Talon chucks loosing their grip on a tenon unless the piece has been in the chuck overnight. I think the Vicmarc chuck is a fine example of precise machining. I am just not a big fan of dovetailed jaws in a chuck. There are too many variables which can be introduced by the turner when forming his tenon which can affect the quality of the grip on the tenon by the chuck. Possibly some or one of these variables are causing your problems with the chuck loosing its grip.
Re: Might be jaw shape, or torque problem
John Lucas
>Ken
Did you put a shoulder on the tenon. Chuck jaws work best when the work piece sits firmly on top of the jaws as well as inside their grip. The shoulder keeps the piece from rocking. The rocking, even slightly makes the jaws dig in and compress the wood. This makes them loose.
