On eBay, I bought a used Sandvik Coromant RA100 face mill, 4" diameter,
uses a 1.5" shell mill arbor, and has six carbide inserts.

The six special hex socket setscrews that tighten the wedges that hold
the inserts are a little worn, and slip on some hex keys. What's
special is that they have both left-hand and right-hand threads on them,
so tightening the setscrew pulls the wedge deeper in, fixing the insert.

I bought a Bison R8 to 1.5" arbor for it. Very pretty piece of iron.

Anyway, the Millrite MVI vertical mill with 1HP 900rpm pancake motor has
no problem spinning this face mill in aluminum, at least on pieces 2"
wide, and leaves a mirror surface.

Have not tried steel yet.

Joe Gwinn