Hot take: that time I spent 3 months chasing a chatter issue on a Haas VF-2 and it was just the workholding

Last June I was pulling my hair out over a 40 thou finish on 6061 until a guy at a trade show in Chicago asked if I'd checked my parallels were even clamped - turns out one jaw had a 5 thou lift from a burr I never saw.

2 comments

2 Comments

the_robert1mo ago

Had you checked the jaw faces with an indicator before you started? Always chase the small stuff first. A 5 thou burr will ruin your whole day and make you think the machine is junk. Sometimes it's the stupid things that bite you hardest. Did you end up finding that burr with a file or a stone?

blair_green861mo ago

Man that 5 thou burr story hits close to home. @the_robert I had basically the same thing happen on a 2018 Haas VF-3 last fall. I was chasing a 20 thou finish on some 7075 parts for a prototype run and swapped tools, changed feeds, even messed with the coolant pressure. Turns out one of my standard Kurt vise jaws had a tiny chip wedged under the stationary jaw from a previous job. I found it totally by accident when I was cleaning out the vise with a brass brush. I checked the jaw face with a test indicator after that and it showed a 3 thou lift in one corner. Stoned it down for 30 seconds and the chatter just vanished. It's crazy how the smallest things make you think the machines alignment is shot when its just a speck of junk.