Tim Wescott wrote:

How does one go about sharpening an end mill? Any web pages on how to
do it? At the last place I worked I noticed a mobile sharpening service
van lurking around the model shop door once a week -- is this something
that even the pros routinely farm out?

And finally -- how do I, the home machinist with a need to sharpen one
or two end mills a year, go about getting them sharpened? Do I just
need to make friends with a machinist, are there places I can drop them
off? Buy resharpened ones? Where? Buy new ones from McMaster and
throw the old ones out?

If you have a surface grinder then you can do a passable job on the
end of an end mill by using a 5C end mill grinding fixture. If you don't,
then I suggest you look up "tool and cutter grinding" in your Yellow
Pages. Getting an end mill sharpened usually costs from 25-50% of new
and if you just get them sharpened on the end then they will still be
the correct diameter. "Resharps" have usually been ground on the periphery
as well as the end. They're good for lots of stuff but unless you're real
sharp with a micrometer you have to deal with some uncertainty as to your
cutting tool width. There are techniques to handle this, of course. - GWE