From: djb@invalid.com   
      
   On 01/03/2025 00:37, Bob La Londe wrote:   
   > No, I didn't put the lathe in reverse, except when I meant to anyway.   
   >   
   > I bought a new parting tool, and some new parting inserts for it that   
   > were supposedly optimized for high chromium and stainless steels.  I   
   > broke a lot of inserts.   
   >   
   > I went back to an HSS parting blade, but I used one 3/16 wide (yeah   
   > really) and ground a chip breaker in it.  Then I polished by hand with   
   > a diamond hone.  Turned the lathe speed way down, and cut several   
   > pieces of 1.5in diameter 416 without much issue.  It does need a drop   
   > (just a drop) 8-10 times during the cut, but it did the trick without   
   > a lot of excitement.   
   >   
   > The chip breaker didn't always break the chips, but it did curly them   
   > up nicely when it didn't.  I didn't have any wild death metal flying   
   > around in my face.   
   >   
   > I'd really like to be able to due this process faster, but atleast   
   > some of my customers are opting for the cheaper aluminum inserts.   
   >   
   > Its not a heavy lathe, but its not a toy either.  Its got a 14 inch   
   > sling, 3HP motor, and weighs right at 2000lbs.  The only thing I   
   > thought of is swapping it out to a 3phase motor so I can change the   
   > RPM on the fly as the diameter decreases. Yeah, I know a real lathe   
   > that size would probably weigh twice that.   
   >   
   >   
   What brand parting tool and inserts were you using? I've got a Hertel   
   insert parting blade and inserts, 3mm wide made in Germany, and  have   
   never broke one but have wore a few out. Lathe is Harrison M300 about   
   1450lbs. I have experienced issues with cheap parting/grooving tools   
   where a few inserts crumbled rather than cut, had to change them until I   
   found a good one that would do the job, I expect that's why they were cheap.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)