I have only used 30 degree as the steepest. I did notice some similar issues with it before I bought some Tormach tool holders. Since then, no more issues. You need to keep collet and spindle socket clean and lightly oiled as mentioned. My mill is likely between a Tormach and X3. Therefore I don't take huge DOC's. About .05" is the most on alumunim. 6600 RPM spindle. .025" on steel. The only high helix is used on aluminum from time to time. I have used it in my trim router too with better results than through the spindle. The higher spindle speed likely had something to say about it's preformance.
I sure hope you get it fixed up. Tool slippage is is an unhappy situation made even worse under cnc control.
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Lee |