I finally snapped a 1/2 inch end mill on a simple contour cut in Seattle last Tuesday

Was running a routine aluminum job, 6061, nothing crazy. The tool was a 3 flute from a batch I've used for months. Feed rate was normal, but the chip load must have been off because the tool grabbed and snapped about 2 inches into the cut. I had to redo the whole program with a fresh tool, then dialed down my feed by 15% and added a peck cycle for the rough passes. Has anyone else had a tool fail on a part you've run a hundred times before?

2 comments

2 Comments

wren3071d ago

Snapped my last good end mill trying to save two minutes on a part I've run 50 times.

lily57421h ago

Had a buddy who did the same thing on a CNC lathe last month. Pushed the feed rate way up thinking he could shave 90 seconds off a run of brass fittings. snapped the tool clean off and it gouged the hell out of the part, plus he had to spend an hour cleaning up the mess and reordering inserts. He said it cost him more time in the end than if he'd just run it normal.