Bill Janssen wrote:
Harold and Susan Vordos wrote:
"Bill Janssen" wrote:

Travers has a 6 inch 4 jaw chuck that I am interested in.
My lathe is a Jet 9X20 with a 1 1/2 inch spindle. The 4 jaw
has a 1 1/2 through hole and I am wondering if there is any
chance of interference when I put a back on it. I assume (I
know) that the back will be thick enough to keep the chuck
away from the spindle. Or should I not be concerned.

Bill k7NOM

I'm not sure I understand your concern, Bill. The backing plate for your
chuck will have a hub that contains within it the proper thread for your
spindle. The hole in chucks tends to be larger than the hole in spindles
so you can chuck up larger diameters as deeply as possible in the chuck.
As long as the hole through the chuck is larger than the hole in your
spindle, and the backing plate is large enough to fit that particular chuck,
I can't imagine where you'd run into problems, particularly if you're going
to machine the back plate to fit. If I'm not understanding you correctly,
please ask again, and try to specify your exact concern. Otherwise, I
wouldn't be too worried about buying the chuck----buy it and enjoy.

Harold

Ok Thanks. My lathe spindle is 1 1/2 X 8 and the chuck ( without
backing plate) has a 1 1/2 hole. If the chuck had a larger bore then
I would not have been concerned. I have to get a backing plate
and machine it to fit. All seems well except I was wondering if the
1 1/2 inch bore was sufficient

The 4 jaw that came with the 9X20 is not very satisfactory and I was
looking for something better.

Thanks again.
Bill k7NOM

The original 4-jaw is an old-style design however some people like it
because
it is so thin and also inexpensive. The hole in your spindle is around
3/4 inch. The size of the hole in the new chuck is fairly irrelevant.
Make sure you verify your spindle thread before ordering a backing
plate. Most 9x20's have a metric spindle thread.
You might consider a visit to http://groups.yahoo.com/group/9x20Lathe/