I've made a short section (12") of hard line for a MW dish feed. It's no
easy task! size relationships are critical and there's no easily available
material for the center conductor the right size for 1/2" copper pipe. I
ended up using hobby brass tubing for the project. The transition between
the center conductor and the connector is a bit finicky, too. Forming the
taper is a pain! The return loss is 7 at 3gHz, not great, but usable. In
short, the suggestions about CATV hard line are good ones, The 3/4 " works
up to 5 gHz with reasonable losses and that's with home brew connectors.

Good luck!

Phil, KB2HQ

"G.Beat" wrote in message
news:J_g%a.152188$o%2.65532@sccrnsc02...
With so much 1/2" and 3/4" end of reel scraps at your local cable TV
franchise (most for free - to cart away) -