On Sun, 04 May 2008 12:37:12 -0500, Jon Elson
wrote:

Bill Schwab wrote:

This should help:

http://www.practicalmachinist.com/vb...d.php?p=856062


It did! When they refer to indicating "the cone," is that inside the
chuck "below" the jaws? Correct me if I am wrong, but that seems to be
overkill with a 3-jaw chuck??


You said something about indicating the rough surface of the
chuck ID. If thre is no ground taper on the back ID of the
chuck or backplate, then I really don't think it can be called a
D1 mount.

The document in the link above is from Jacobs, so I think it's likely
the instructions are for mounting a Rubberflex chuck and the "cone" is
the seating surface for the collets.

--
Ned Simmons