End mill snapped on a simple contour cut yesterday, had to rethink my speeds entirely

I was running a standard 1/4 inch carbide end mill on some 6061 aluminum at the usual settings I've used for years, around 60 IPM at 10k RPM. The tool broke clean off about halfway through a simple contour, no warning at all. Talked to the old timer at work who told me my chip load was way too light and I was just rubbing the material to death. Has anyone else had to bump up their feed rates significantly after a crash like that?

2 comments

2 Comments

angelac6313d ago

Man, that old timer was right on the money. It's like driving a car in too high a gear - you're making noise but not getting anywhere, and eventually something gives. I've noticed the same pattern when I'm cooking too, like trying to sear a steak on low heat and wondering why it's tough and gray instead of getting a proper crust. Sometimes you gotta commit to the speed and trust the tool to handle it.

the_max13d ago

Ha, I gotta disagree a little though. Not every tool is meant to run wide open all the time, you know? Sometimes you need to ease off the gas to keep control, like using a lower speed on a drill so you don't strip the screw head or burn out the motor. Pushing everything full tilt can work, but it also can break things faster than going slow and steady.