On Sat, 14 Feb 2015 04:15:43 -0800 (PST), robobass
wrote:

I just ordered two 6mm carbide cutters. Maybe I'll try grinding the flutes on one of them. I did notice that my 3mm carbide mill cuts brass with way less effort than the HSS Co. Maybe the combination of carbide and a larger radius will be enough. Two finishing passes too? I don't need a mirror finish, but it's gotta be better than it is now!
Thanks everyone.

Something is funny there. There should be little or no difference in
the "effort" required by a carbide cutter versus HSS. If anything, the
HSS should require slightly less effort, given equal sharpness.

The only reason to go with carbide when cutting brass is if you're
burning your HSS cutters. This is extremely unlikely.

There is one other potential issue, however: Carbide is stiffer. If
the flexibility of the cutter itself is contributing to the chatter,
carbide could help.

--
Ed Huntress