[Greg Perkins]

harder the material=slower the rpms
harder the material=TONS OF MACHINE OIL/LUBE (NOT MOTOR OIL)
the more oil=better cut=longer tool life

regardless to the amount of smoke that you make, the smoke should be minimal with proper rpms....if you hog into the peice and your oil instantly burns up, turn the rpms down and add more oil....

One more thing, is drill smaller holes into hard material first...that means less for the big drill to remove (big drills have less of a angle that enters the material first, thus making it much harder to get in.)

hope this helps