Winston pretended :
Bob La Londe wrote:
"Wayne" wrote in message
...
I need to make some donut shaped shims.

Epoxy it to a sacrificial block, machine to size and shape, remove from
block with heat.


What Bob said, except use Super-Glue cyanoacrylate.
Epoxy doesn't stick to steel nearly as well.

Start with an aluminum backing plate the same X and Y size
as your shim stock blanks.
Clean and degrease shimstock and backing plate, interleave
layers of copier paper between each piece of shim, all glued
up with Super-glue.
A 4 layer sandwich will give you 4 shims per operation.

Use a thick aluminum sheet to clamp the sandwich to cure
each lamination flat.

HINT! Before gluing, exhale to fog the shim. The condensed
water really speeds up the curing process.

Adjust the direction of mill cutter travel clockwise on
the ID and counterclockwise on the OD so that the ragged
edge appears on the scrap material rather than your top
workpiece.

A propane torch on the backing plate will cause the shims
to release from the backing plate. Use Lots Of Ventilation!
Promptly blow out the flame produced by burning superglue.

They turn out very nicely. Use a random orbit sander to
clean off charring on the back of the top most shim, should
it appear.

--Winston

What kind of cutter are we talking about here? I've mostly
have used end mills, or occasionally a counterbore.

Wayne D.