I have used this drill to cut .020", .025", .032", .040" and .050" 6061-T6 as it is for experimental aircraft parts is common. The drill bit lasts about the same as the more expensive ones. I have a day or two to cut before it breaks. Since this is a small diameter drill bit with a long cutting length, you push it like a thicker drill bit. But You also can't push expensive drill bits Runs at about 10,000 rpm at 15-30 ipm, no coolant, no lube They all usually fail due to fatigue so make sure the