ducque wrote:

Since I'm completely self-taught at machining, there are necessarily
big "holes" in my knowledge. Here's one, and I'd like to "fill the
hole"! :-)

I don't know how to accurately make a very thin part -- for example,
something akin to a washer, or a very short bushing.

It's easy enough to accurately turn the part, make necessary shoulders,
etc. But what about after the piece is "parted off"? The desired part
will be too thin to hold effectively in a vise to mill to its final
thickness (imagine needing a part less than 0.050 thick, for example).


For example, using my milling vise and parallels, I cannot effectively
grip and strongly hold anything less than about 0.065 thick.

What do people do in these situations? Thanks.



There are a couple ways to attack this. One is to make the stock the
correct
thickness first, then drill a hole in it. Now, grip a bolt in the lathe
chuck
with the threads sticking out. Run a nut on the bolt, the stock with hole,
and finish with another nut. Tighten the nuts together with 2 wrenches.
Now, you can turn the OD as desired. I make a number of odd spacers,
etc. like this.

If the entire part needs to be concentric and the faces parallel, make
an arbor
from random stock, by chucking in the lathe and facing true. Superglue
the stock to the arbor. Perform all operations, facing, ID and OD turning,
etc. Both faces will be parallel to the extent the superglue formed a
uniform thickness film. When done, pry thicker parts off the superglue,
or use Acetone to dissolve the superglue and release thin parts.

Jon