counterbore

I am in process of making a part & could use some pointers.. (Lathe is an Atlas QC54. Am using HSS tooling) The part is a ring, 2.25 OD x .75 ID x 1.00" long/thick. On one side is a recess, or counterbore, of 1.625 dia x .875" deep. What would be your choice of HSS cutting tool and process to...

Hi All, I need to counterbore 6 @ 9/16"diameter x 1/2" deep holes in a cast iron part. Question is, do I need a carbide/cobalt counterbore or can I get away with using HSS? I have drilled and tapped cast before but never counterbored it. I don't want to waste money on an expensive tool if I...