My experience is that the drill speed is the single most important
issue. I wrote off several drill bits while drilling a mast, and
my supply of four High Speed Steel bits didn't even get through the
first wall (something like 3.5 mm or 9/64").
I then borrowed a drill that turned at something like 500 RPM
(instead of the 1300 on the previous drill), and managed to complete
four holes with a single bit, identical to the ones that had been
* Turn sloooooooooowly.
* Lubricate generously. If you see smoke, you're doing it wrong.
* Don't be tempted to push. Apply light pressure, and wait. The
resulting wait is considerably shorter than a trip up and down the
tower and/or replacement of the drill bit!
Chris R. Burger
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