Background. I have an old Index 40 vertical mill. It isn't in the
greatest shape, but it is usable and I'm gradually cleaning up some of the
problems from extended storage in a humid garage with a leaky roof.
The main use for it is cleaning up the faces of billets after hot forging
them. (I'm making pattern-welded [or damascus] steel. Looks like this
when it is done:
http://i166.photobucket.com/albums/u90/torin3/seam2.jpg )
The billets have an irregular surface and are covered in firescale. I've
been using a 3 insert cutter with an R-8 shank that uses TPG inserts.
Obviously it isn't that great of an option, and the TPG inserts wear down
quickly. One of my coworkers pointed out that octagon and round inserts
are much stronger, and handle interrupted cuts better. So, I'm thinking
about switching over.
I've seen a couple of insert mills that might be worth switching to. One
of them is the 'freedom' cutter by Mil-Tec. It can use
round/octagon/square inserts on the same body, has an R-8 shank, but it
seems to use proprietary sized inserts, and they want between $10 and $18
per insert.
I've seen a few others that use standard 85 degree inserts, APKTs, but
they only have 2 cutting positions, not the 8 that the octagons have.
On the plus side, I've got permission to raid the used insert pile at
work. They've been used, but they get pulled when they are still usable
to me, as I don't need a great surface finish, just mostly flat so that
the billet faces meet up for the next forge welding run. I just need to
return them when I'm done with them for recycling. So, I can probably not
need to pay a lot for APKT or OECR inserts, provided I can get a indexable
mill that fits the ones we use here.
I guess the advice I'm looking for is:
1. Should I got with octagon inserts?
2. If so, is there a non-proprietary option out there that uses standard
sizes, or suck it up and go with the 'freedom' cutter?
3. Should I go with the APKT option, and buy on ebay or use from the
recycle pile at work?
4. Is there a better option I missed that falls within my $200 budget?
Thanks!
Todd