Roger Shoaf wrote:
"RBnDFW" wrote in message
...
A friend is coming over tomorrow night so we can mill some BMW calipers
for his Porsche. Now, I'm no machinist, I guess I'm more of a machine
collector. I just don't want to mess up the calipers, and I'd also like
to not look like a klutz G

So, we need to mill .125" off the mounting ears on these iron calipers.
I'm guess these are some sort of cast steel.
I'll be using most likely a Enco Mill-drill, possibly a Burke MVN if I
can get it wired.
I have a 1.125 indexible face mill, with two triangular carbide inserts.

What speed should I run it at, and what depth of cut?

Play with some scrap first to get a feel of the machine.

A mill drill is going to have limited speed selections any way and if you
are using an 1 1/8" mill you are probably going to be on the low speed side.

Another factor is the rigidity of the set up and the machine itself. If you
are running too fast and taking a deep cut and something slips a bit you
have just scrapped the part. When I am unsure of the set up I tend to have
a finger on the part where it meets the table. That way if it starts to
move you feel it.

Listen and watch the cut as it progresses. Be wary of changes in chip color
or changes in sound.

Not sure of the lowest speed on this, but I suspect something around
300. Still OK with the carbide tool?
I also have flycutters in 4 sizes, biggest probably 1.5"
And HSS endills up to 3/4", probably larger, 2-flute & 4-flute.