"Grant Erwin" wrote in message
...
I have a need for some 4" circles of 1/8" steel. They have to be pretty
flat. They will wind up with a central hole of 5/8". (Tolerance here is
about 1/32", not really machinist tolerances.) If I could think of a clever
way to hold them by the 5/8" hole really solidly, I might be tempted to try
grinding up a trepanning bit - how hard can it be?

I suppose I could try cutting them with a circle template and a plasma
cutter, or I could make up a bandsaw circle jig and try cutting them on
the bandsaw (don't have a 24tpi blade though) or even borrow someone's
hole saw and try banging them out in one go on the mill. I don't have
access to a blanking press. I only need 3, so it isn't worth having them
laser cut.

I have a few days before I need them. What's the easiest way to cut these?

Grant Erwin
Kirkland, Washington

How about this approach:

1. Rough-cut the circles (a bit oversized) with your favorite cutter
2. Drill a 1/2" hole at the centerpoint of each circle blank
3. Cut the head off of a 1/2" bolt (with a smooth shank) and chuck it in
your lathe
4. Put a nut on the bolt and run it up tight then put the 3 blanks on and
use another nut to clamp them. [Washers optional]
5. Turn to size
6. Re-drill center hole to 5/8"

You DID say you wanted EASY, didn't you?