I am posting to this Haas forum because it has the most viewers. I ave been thinking of buying a Haas swiss lathe, so my interest is sincere, though this is a general question.
I am parting a ss303 3/8 rod with 1/8 hole down center and length of 2.5 inches beyond the parting plane. Currently I am using a .090 solid carbide brazed tool that I have ground a 20 degree angle on with a diamond wheel. It leaves a burr on the parted piece. This is probably due to the fact that the long piece wobbles and tears itself away prematurely from the chucked stub.
I have thought of a "concave restrainer" consisting of a 180 degree half cylinder that is positioned to be close to the piece when the parting tool is close to cut-off.
On to the tool itself. I have an Iscar grooving tool and another tool that takes GTN-L2. I have thought of grinding an angle on the iscar insert or the GTL.
I worked with a cnc expert a few years ago, and he achieved good parting by varying the spindle speed right before parting. As I recall, he upped the rpm's and slowed down down the feed. Got rid of the burr. But that was a stubby part, and I am working with a 2.5 inch part now.
Any ideas? Thanks in advance.