Smithy Granite

Ok - my dad told me to look into these machines; he used to be a
machinist and had heard of them a while ago (this was 10 years ago or
so). Anyhow - has anyone retrofitted one of their 'CNC compatible' units
with steppers and drivers?
I am thinking of getting one with their payment plan, and retrofit it
with my hardware. But, I have one question, and it's based purely on
ignorance; I need to cut 3/8" to 1/2" flanges; will a CNC mill do it
with the right bit? I feel like a dumb ass because I don't know the
answer, but that's the only reason I built the plasma CNC. While the
system, as most of you have seen thus far, looks pretty good - the
little things are starting to get to me; its accuracy just isn't where I
want it - that's the nature of the beast with a plasma cutter though.
If someone says I can use the Smithy as a milling unit to mill out
steel, I'll order one on Monday. I've got a product, that I've been held
u on because my CNC isn't working - and I've had to delay it 3 weeks
almost because I can't get the flanges cut.
Anyone?
Thanks,
-Chris Clough