Folks,

This is my first foray outside machining Delrin and Aluminium. To some extent, I’m still a CAD jockey. I need a sanity check for the material and the heat treatment for this punch and anvil pair.

  • Anvil. 0.4" [10 mm] O.D. Holds and locates one of the work parts. The anvil is threaded into the jig, and it doesn’t move.
  • Punch. Slides up and down. The force on the punch is up to 1.2 ton. There is not cutting. Just pressing of the two work parts together.


Here’s a [somewhat simplified] sketch. If you click it, you should see a larger picture.

Attachment 208298

I guess, one of the failure modes for parts like this is that they can flare out under pressure and, as a result, get stuck. Perhaps, also there’s some opportunity for the punch to wear as it slides in the jig.

As I’ve mentioned above, I need to identify the material and the heat treatment. My present thinking is to use 12L14 steel, which machines very well. Then carburize and case-harden it to a depth of, say, 0.04” [1 mm].
Can this work? Do I have to use a higher grade of steel, which can through-harden, but is also harder to machine?

Any suggestion, insight or reference is really appreciated!

Cheers,
- Nick