MT Sleeve?

[Choiliefan]

...and the blue chips will fly.
Which is a good thing.

 

[bakrch]

Guys I finally got around to getting a sleeve/reducer for my lathe but! Its a 1 1/4 OD/MT#3 which is great I think.The OD that I need is 1" to fit the turret but I receive info that I could take an 1 1/4 sleeve turn it down to 1" which then all my #3 MT drill chucks and live center with work.OK here's my problem,taking a few passes I notice that about first 1/2 all is good then it seems that I hit the harden area or harder area plus an interrupting cut and after the interrupting cut its seems its harder.Well my question is,do I have the right carbide cutting insert for turning down this harden sleeve?If not could someone direct me to what I need to order?This is an AXA tool holder and tooling set that I pick up from Shars and the insert is what came with it.I am lubing the part,hand feeding slowly at a low rpm setting.Thanks for any adviceView attachment 304739View attachment 304740

Inserts that have a molded edge like that tend to push/bounce away from harder materials. I would use an insert with ground periphery, something like a CNGP or CPGM. I'm not terribly familiar with trigon inserts like that, but the third letter of the insert identification tells you how the edge is prepped (XXGX). So, WCGT maybe? 100-150SFM should be fine.

I do a bunch of hard turning, with interrupted cuts like that.

This part here is 100% 56-58 HRC 440C (well, except for the stem that is screwed into it, that is Nitronic 50).