I'm running a Leadwell V25 with a Fanuc 21M controller and an 8K rpm spindle . It breaks every single bit under .0625 I use in it. I've had the runout checked on the spindle taper ( he said it was around 25 millionths of an inch) , checked the runout on the tool holders in question ( none are over 2 ten-thousandths ) , checked the bit shafts themselves ( under 5 percent of bit diameter in every single case ).
Bits break when I run a .0313 2-flute end mill at 10, 18, and 25 IPM at a depth of cut at half a diameter ( .015625 , a 64th of an inch ) in soft aluminum. This is the cheap extruded stuff you get at Lowes, the kind where if you yell at it too strongly it knots into a pretzel. It breaks in rosewood, ebony, and oak at the same or less IPM and the same RPM. I've run 5 IPM or less at 8K rpm through oak at a depth of a sixtyfourth of an inch on an engraving bit and chipped the tip off in the first 30 seconds.
So, anyone got any ideas? I'm thinking that the math for the right chip load for the aluminum at this depth puts the IPM at 24 for an 8K RPM spindle speed. Snap.
Am I really going to have to get a speed-up device just for the smaller bits?
Bits break when I run a .0313 2-flute end mill at 10, 18, and 25 IPM at a depth of cut at half a diameter ( .015625 , a 64th of an inch ) in soft aluminum. This is the cheap extruded stuff you get at Lowes, the kind where if you yell at it too strongly it knots into a pretzel. It breaks in rosewood, ebony, and oak at the same or less IPM and the same RPM. I've run 5 IPM or less at 8K rpm through oak at a depth of a sixtyfourth of an inch on an engraving bit and chipped the tip off in the first 30 seconds.
So, anyone got any ideas? I'm thinking that the math for the right chip load for the aluminum at this depth puts the IPM at 24 for an 8K RPM spindle speed. Snap.
Am I really going to have to get a speed-up device just for the smaller bits?