wrote in message news

God I'm surprised only one guy told you the right answer... You use a
"step bit", Home Depot has them, they are cone shaped and cut 1/16 or
1/8 inch per step, you stop pushing when you hit the 3/4 inch step.
They cut very fast, clean, and round especially through aluminum, but
set the drill slower for aluminum. They are not cheap bits but well
worth the money for metal fabrication jobs.

They probably didn't tell him to use a step bit drill for two reasons.

First they only go to 1/2 inch.

Second if you find a 3/4 inch step drill the depth of each
land is less than 1/4 inch

Think about it. He wants 3/4" holes. The largest step on the bit I referred to is 3/4". Also the
bits are made at least as large as 1 3/8". I have several different sizes and varieties of
these.....Paul