Tried a faster feed rate on my Haas VM3 and it backfired

Everyone says push the feed rate to 200% to save time but I tried it on a aluminum job last Thursday and my tool chatter was so bad it ruined the part. Spent 2 hours reprogramming the speeds back down and wasted $40 in material. Learned that dialing in the right chip load matters way more than just cranking numbers up. Anyone else find the 'go faster' advice doesn't always work?

3 comments

3 Comments

max41515d ago

Did the same thing myself a few years back on a similar machine. That whole "just crank it to 200%" advice sounds good in theory but it totally ignores things like tool stickout, part rigidity, and just basic physics. You gotta work your way up slowly and listen to the machine. Sucks you wasted money but honestly that's how most of us learn this stuff the hard way.

johnson.jason1d ago

Ngl "basic physics" is right. But it's really about harmonic vibration, not just physics.

johnson.jason15d ago

Used to think the "crank it up" crowd had a point until I snapped a 3/4 endmill trying to run a .200 DOC at full speed on a Bridgeport. Stuck out about 4 inches, part was vibrating like a tuning fork, and I just ignored it. Chunk of carbide flew past my head and cost me $80 plus a replacement insert holder. That was the day I learned that feeding 200% is a recipe for disaster unless you're cutting butter with a stub tool and a rigid setup. Now I always start conservative and listen to the chatter before touching the override.