- Joined
- Jan 22, 2011
- Messages
- 8,031
Paul likely has the root cause identified. If you were watching in slow motion and under magnification, you would probably see chips "welding" and building up on the tip. When the cutting stresses are enough, that little blob of metal gets knocked off and any pushoff you were seeing is instantly removed as the tool digs in for a revolution or two. Then the process repeats itself, at a sort of random interval. It's part of dealing with that particular material. You could use some of the suggestions here to limit this effect, but unless you have enough machine (and trust) to make a pretty hefty cut at high speed/feed with coolant and carbide, you will find it difficult to impossible to machine a nice finish.
btw, are you sure about the material? From here it doesn't look like hot rolled material. And I rarely see people running HRS in a collet. Generally it's not round enough to hold properly. Looks more like CRS to me, but that could be my eyesight.
btw, are you sure about the material? From here it doesn't look like hot rolled material. And I rarely see people running HRS in a collet. Generally it's not round enough to hold properly. Looks more like CRS to me, but that could be my eyesight.