Chuck mounting question

Hi All,
I am nearing completion of the restoration on my recently aquired 10"
Sheldon lathe. As such, i am looking around at my tooling and
accessories to see what i can transfer over to use on the Sheldon. The
lathe came with what looks to be a decent 3 jaw chuck. I also put my
hans on (from a different source) a nice old SB 4 jaw. The backplate
on the 4 jaw appears to have the same thread as the Sheldon spindle,
except that the portion of the backplate that threads onto the spindle
is not as deep. As a result, the spindle threads will hit the back of
the chuck before the boss on the back of the backplate seats onto the
spindle face. There is a photo that shows the chuck on the spindle as
far as it will go, here:
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This shows the 2 different backplates, the 4 jaw is on the left:
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Note the difference in the depth of both the threaded and the
unthreaded portion of the backplates.
My question is this: is there any reason that I could not just add a
"ring" of sufficent thickness to the 4 jaw plate (screwed or pinned in
place) that it would add enough depth to the boss to allow it to seat
properly? Or would I simply be better off getting or making a new
backplate? Any other ideas?
Thanks for any thoughts,
Reply to
Al A.
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I would make a new back plate. Although I can't tell from the picture, but it looks like the 4 jaw chuck is one piece. The 3 jaw does have a back plate on it which I can see from the pictures.
Reply to
Richard W.
Thanks for the reply, Richard. It is not clear in the picture, but the threaded portion of the 4 jaw is actually a seperate piece. Not a backplate, per se, but it can be removed and either a replacement made, or a more typical backplate used in place if it.
-Al A.
Reply to
Al A.
My wood lathe chuck came with a spacer ring to seat the chuck on the spindle face. Works fine. Feel free to turn one for yourself.! Bugs
Reply to

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