I have a piece of 1", 1/8" aluminum angle iron that is 18" long and 1/8"
thick. I want to drill sixteen holes in it, in a straight line, each hole 1"
away from the other. I also have a flat piece of aluminum that is 2" x 18" x
1/8" thick. I want to drill two rows of 16 holes in that one. All holes are
1/4" in diameter.

I've scrapped enough metal to set my ego aside and admit that I need help
with the very basics of basics. How do I make the measurements, mark them,
and then drill the holes?

Thanks!