I stopped flying through feeds and speeds around 18 months ago

For like 5 years I would just crank the RPM and push feed rates to whatever the machine could handle without screaming. Then last June I had a 3/4 end mill snap on a simple aluminum part and it shot a chunk of carbide across the shop. That made me slow down and actually calculate chip loads per tooth. Now I spend 10 minutes with a calculator and reference charts before every job instead of guessing. I cut a little slower but I haven't broken a tool since that day. Has anyone else had a crash that made them totally change their approach to speeds?

2 comments

2 Comments

rubysingh1mo ago

That article in Modern Machine Shop about harmonic chatter really opened my eyes. It explained how feeds and speeds are basically a math problem with vibration and tool deflection built in, not just a feel thing. I still listen to the machine but now I back it up with actual numbers from a chip load chart. Calculators just take the guesswork out of it before you even touch the start button.

daniel_martin1mo ago

Were you measuring tool deflection before the crash or just running based on sound and feel? Cause I wonder if the numbers wouldve caught that failure early enough. I run a similar setup now with charts but still trust my ears more than the calculator sometimes.