If you're machining 303 stainless on a sliding headstock machine and have these kind of issues, definitely look into material. I'd be using Ugima 303XL or their Ugima 303UX (depending upon application fo the finished part.) That material is a bit more money than standard stuff from say Castle, Yarde or others, but well worth it in machinability, tool life, and overall productivity.
That grade from Sandvik is OK, but you'd do much better with their GC1020. Expect that grade to last all day at 500sfm or more. With sliding headstock machines, you're always better-off to take single pass cuts so you don't back-up the stock and risk damaging the guide bushing on a burr, or worse, have the part come off the carbide and start whipping around. This make choice of insert top form geometry (chipbreaker design) difficult, but not impossible. If you switch to the Ugima material, chip control will be a problem of the past, I assure you.
You are using what I consider to be the very best all-around cutting fluid for a Swiss machine. Expensive, but worth it. Best of luck to you.  |