That crash that cost me 40 minutes last Friday

I messed up a setup last week running some aluminum 6061 parts on a Haas VF-2. I was at my shop in Portland and goofed the tool offset on a 3/8 end mill by .025 inches. It snapped the tool and dug a groove into the vise jaw before I hit the e-stop. Most guys say you gotta start the whole program over after a crash like that, but I just re-zeroed my workshift and swapped the tool and ran the rest without issues. The part was still in tolerance on the micrometer. Has anyone else saved a run after a crash like that or am I just lucky?

3 comments

3 Comments

sean_cooper581mo ago

You're not just lucky, I've done the same thing more than once. If the crash is clean and the work offset is still solid, you can usually just rezero and swap tools. The key is checking if the part moved in the vise at all, even a few thou can throw everything off. I always run an indicator over the first feature after a crash to make sure nothing shifted before committing to the rest of the program. You gotta trust your gut with those tools too, a swapped endmill that looks fine might have micro fractures from the snap.

tessa_murray1mo ago

Micro fractures from a snap, you have to be kidding me, how do you even sleep at night?

kelly.charlie1mo ago

Machines don't always tell you when the spindle bearings are shot after a hard crash either, that little vibration you feel at 12k rpm might be the start of a bigger problem down the road. Nobody talks about checking the drawbar force after swapping tools either, a loose holder can give you tool pullout halfway through a finish pass.