Learning the HSS ropes

[Batmanacw]

I must admit my first experiences with turning were with 303 and 316 stainless for food processing equipment. Finish was paramount so we had to learn to grind the tools to make finishes that would be acceptable to the inspection department. It was a steep learning curve. The instructor was a highly regarded craftsman from the old country. He demanded quality, but was willing to take the time and effort to be sure the goals were met.

I'm going to try a few other steel types and I could easily try out some 303.

The proper rpm for the 12L14 I was cutting today was 340 rpm. I sharpened the tool sharp enough to pop hairs. Polished to 320 grit on a stone. No burr and a very keen edge.

So far only a larger radius helped. I'm thinking it's just the steel type that was frustrating me.

I'm pretty sure I've got some 1215 and 1045 I can try.

 

[T Bredehoft]

Which angle on top? The back rake away from the chuck? The tool holder gives around 15⁰ from the par...

It appears that you have between 5 and 10 degrees away from the part on the top of the HSS tool. If I were grinding that, it would be nearer 30 or 35 degrees. That improves the "shear angle."