RBnDFW wrote:

Bill McKee wrote:
wrote in message
...
On Apr 21, 6:18 pm, RBnDFW wrote:
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?

I checked and it is cast iron. These came off a BMW 320I, std model.

I would probably take a pass at about .070 depth of cut. Then measure
it and make the next cut to get it to size. It sounds as if you have
a very small amount of metal to remove. If that is the case just use
a low speed and do not worry about the optimum speed to do the job in
the least amount of time.

Yes carbide does give you a better surface finish if you have a higher
speed, but he is doing this on a Mill Drill. So I would use a slow
speed.

Still OK with carbide, right?

An 1/8" I would use a grinder or file. Depending if it does not have to be
a precision flat surface.

It does have to be precision. This surface locates the caliper in
relation to the rotor, so it has to be parallel and flat

Be sure to spend the time with a dial indicator to locate the part and
ensure that the existing reference surface is fully in plane before
making any cuts. The cuts will be the easy part, the setup will be the
difficult part.