postronics
Plastic
- Joined
- Oct 25, 2011
- Location
- canada
We are fairly new to CNC lathe, as we just got our first machine a Milltronics ML16/40 recently. We are familiar with mills as we have had a few for years here at the shop. We are having some massive vibration/chatter issues when boring, and don't know if its our tooling, set-up, feeds/speeds, or just the lathe itself. The part we tried to cut was a piece of 6"x3" mechanical tubing. We needed to take it down to 5.5" OD x 3.152 ID x 4" long. We put the stock in the bison 10" 3 jaw. The pc was 6" long to start. We cut the OD with no issues, when moving to the ID we had tons of chatter to the point we hit the feed hold to keep from breaking the tool. We had the spindle at 400FPM with a .010" IPR feed for the roughing. depth of cut was .030". We used an 1-1/4" Kennametal boring bar with a DNMG432MP insert. We also tried turning the feed down all the way to 50% with no improvement. Our boring bar was sticking out just enough to make the cut. Any ideas? We gave up and finished in the manual, but i would really like to get this machine figured out.