"Daven Thrice" wrote in message
news:9Ik1d.263527$sh.202086@fed1read06...

"Richard J Kinch" wrote


Straightedge and carbide scriber for the lines. ($20)

OK, I'm working with 1" extrusions, that are 90 deg. angles. I want to
mark
a hole that is 1/4" in from one edge. The only "straight edge" I can think
of using is a metal ruler, which is an 1" wide (or so). I'm wondering how
to
clamp the ruler to the work piece good enough for me to be able to drag
that
scribe along the straight edge without the straight edge shifting.

I have one of those laser straight line things that you use for a level.
I'm
thinking about taping the work piece to the wall and using the laser level
to create a straight line. Hmmm. Don't know if that will work. If it does,
though, I can then tape a ruler just below the straight line and then mark
of X's, which can then be center punched. This sounds like a lot to go
through, though. I'd rather just clamp a straight edge to the aluminum,
but
how is that properly done?

Clamp a piece of straight stock to the drill press table as a fence to keep
the holes in line. If you want to, put a tape measure on the straight edge
so you can advance the angle in 1" increments.

Check out any woodworkers group about drilling holes for shelving for more
ideas..