In article . com,
says...
I'm tired of trying to find 1/2" thin wall, round tubing (not pipe).

I get my 4130 tubing from Aircraft Spruce. 1/2" x .028 is around
1.50/foot. www.aircraftspruce.com

--
is Joshua Putnam
http://www.phred.org/~josh/
Braze your own bicycle frames. See
http://www.phred.org/~josh/build/build.html