I set my bridgeport up to cut a thin slot in a piece of steel. So far I
have only broken bits.
I dont know much about hardness but the material I am using has a black
coating. Not sure what that is. But I started off with a 1/8" endmill
taking very light cut at a very slow speed. I am having no luck.
Additionally, I need my slot to be deeper than the endmill itself.

What I am doing is setting up a 2 brackets to hold a 1/8" x 1.25" x 12"
long cutting bar. I am sure there has to be an easier way but it might
take more pieces than cutting from one.

Any suggestions?
Thanks