"Tim Shoppa" wrote in message
oups.com...
wrote:
I need to to get a positive feature which is 100um diameter and
500um
long (a very small rod) with milling machine. I can use aluminum or
steel.
I wonder if it is possible? If so which material is better? I think
aluminum
is easy to cut but may be too flexible for a feature like this. Any
suggestions
on the cutting parameters are highly appreciated.

100um = 0.1mm, right? That's a really short piece of 38 gauge copper
wire, or of 6/0 music wire. I'm guessing it might be available in
aluminum and brass too (but don't see it in any of my catalogs.)

Tim.


Possible? Yes, but it requires one hell of a lot of patience. You made
no mention of the tolerance required, however, so that could be the limiting
factor. A boring head with the properly configured tool will easily make
the cut. I'm assuming the "post" will be at a right angle to the surface.
If material isn't a serious concern, you may enjoy making it from 12L14,
which will machine without tearing and leave a decent finish. 7075-T6
aluminum might also be a good choice, as well as 2024-T351. It likely
goes without saying that light cuts are in order, and a fine feel.

A permanent stop should be set, along with an indicator so you have an idea
where the tool is relative to the part in question. I'd suggest a finely
honed HSS toolbit for such a challenge, not carbide. You'll need
reasonable positive rake and virtually no radius on the tool. Measuring
the diameter will be challenging, but it's possible a comparator could be
used.

How are your eyes? Seeing the part and the cut will be a big part of the
challenge.

Harold