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Set-true chuck types


Dec 4, 2010
McClure, PA 17059
I like having all types and sizes of chucks. Retired and do odd work usually something other shops can't do (like metric threads but any lathe will thread metric). So having all sizes and types of chucks is of value to me so I keep an eye on ebay and HGR. I have seen at HGR 3 jaw chucks that have what looks like a set screw behind every jaw but not far back enough to be set-true. Is there a style that the set screws move the scroll plate? Not sure but that might work!
Post a picture of what you describe.

Have you seen the German-made "System Wescott" chucks? I also have one of that type made in Switzerland. They have a scroll and each jaw has its own adjusting screw.



Here is a youtube on truing the face of a set true..
If one has a thread-on lathe chuck it will rest in the same place each time mounted, if a cam lock then good to place a line-up line and put the chuck on the machine/same pin each time mounted..
The Adjust True does not take away wobble..only truing one to your lathe will do that.
What I call lope-de-lope is the whole part going off-center close to the chuck and the same (180) out a ways.
*Yes if just mounting the chuck and the inside face runs zero you may be good to go..I dress my grinding wheel mount face to zero with a line-up mark (if that mount is only used on one machine.

Wobble is when the error is at one place it is off and out a ways the error is at a different clock position, so wobble is off like pushing two bicycle pedals.

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I have a few of them both 3 and 4 jaw chucks. The have a scroll so all the jaw move together yet each jaw has the adjustment just like the one in the photo. 3 of them are Cushman. I would love to find a Cushman universal/independent 6 jaw chuck, they had one where my father worked. I'm just wondering why I seen a few chucks with set screw in back of every jaw but set screw was in the casting and not near the jaws but ahead of the wrench square so it looked like it was over the scroll.