Broken End Mills
I broke 4 carbide end mills :-(
Spring steel 200 HB
carbide end mill 4 mm, stick out 20 mm, 2 flutes
DOC 5 mm
WOC 4 mm
Suggested feed is 39.46 mm/min, I used half of that.
I had chatter and broke 4 mills and yet the tool torque calculated by HSM advisor is 50%.
What am I doing wrong?