....the problem comes when it's time to remove that stub and face the end. Then I have no place to hold the piece without marring it. If I use one of my MT3 collet chucks, then if the piece is as little as ~10 mils less than the nominal diameter of the chuck, it spins. The MT3 chucks I am using have very little range. And the other concern is I am tightening them up against the inside of my lathe spindle directly. I am concerned that over time I may wear it down. So I think I will keep those for holding end mills and get an E32 system for holding parts. Thanks folks!

Dan


On Friday, November 3, 2017 at 1:00:06 PM UTC-4, Jim Wilkins wrote:
"Daniel Koller" wrote in message
...
Hi Folks,

If I were to buy one of these sets of Chinese made ER32 collets on
e-bay
(https://www.ebay.com/itm/19pcs-ER32-...100005.m185 1)

...what is the range of each collet? With increments of 1/16" can I
hold any size rod?

If I have 3/16" and 1/4" for example, do I need 7/32"?

I see that the 20 piece set that I linked, has incrememts of 1mm.
1/16" is 1.6mm so it seems to me I would have gaps if I only got 1/16"
increments.

Right now I am using a MT3 collet set, but I am finding it pretty
limited. It holds nominal stock sizes just fine, but if I take a few
mils off to clean up the OD before chucking it, the rod slips.

Thanks for the advice!

Dan

p.s. Intended use is on a 1952 Logan 10" (Wards) lathe. MT3 taper in
the head, MT2 in the tailstock.

=============================

In general I've found that only precision ground drill rod that fits
my 5C collets deserves them, a chuck is fine for rougher stock.

If the piece will need to be removed to check fit and replaced on the
lathe it's easy enough to turn a stub on one end to collet size.
-jsw