On Sun, 13 Mar 2005 14:27:18 +0000, Nick Atty
strung together this:

Something along the lines of what I thought, but galv of up to 2"
diameter and painted. You may get away with using 28mm copper for ease
of availability as 2" galv would require someone to manufacture the
joints for you, a commercial heating engineer.

That's another good idea I hadn't come up with. You can hire dies for
putting threads on large diameter pipes can't you?

I would assume so, I live across the road from a commercial heating
engineer so have never needed to hire one! You can get hand operated
ratchet dies or huge electric ones, a hand one is reasonably easy to
use on 1 1/2" and smaller.
--

SJW
Please reply to group or use 'usenet' in email subject