CNC Router cutting some 0.5″ thick 6061-T6
1/4″ Merlin carbide bit (90 point for drilling). Video shows a pretty conservative 70 ipm at 17000 rpm. DOC is 0.100″. Conservative settings.
I’ll kick it up to 100 ipm at 25000 rpm, but need to keep the air nozzle handy to blow out chips, and WD40 as machinging lubricant. That is a Bosch Router, with precision collets (TIR is 0.000 4) with those collets.
Design was 3.1″ for center hole, which I’ll finish on the mill to 3.187″. Measured was 3.096″ (not bad). This is not a Haas, but for the price and to hog out aluminum, works nicely.
Trick to have gotten a nice finish… better clamping, rough cut then do a final pass 0.020″ closer. Had I taken the time to clamp to a 1″ thick plate, pinning with dowel pins, and bolts… it would have a smoother finish. Just a matter of “get ‘er done”
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