On Fri, 4 Apr 2008 09:49:55 -0500, "Backlash"
wrote:

On the construction job I once worked on, the electricians bent aluminum up
to 4" daily with their benders. Of course the aluminum rigid conduit might
well have been a special alloy.

RJ

The vast majority of electrical work you would see in the US is done
with thinwall mild steel Electrical Metallic Tubing, or heavy-wall
seamless (mandrel drawn) Rigid Steel Conduit that is threaded in
standard pipe sizes. Both are galvanized to resist the effects of
water.

Both of those conduits bend up nicely, because the steel allows for
easy bending without failures. You can do it in dead-soft aluminum,
but not aluminum pipe that is many years old - just age alone will
start to harden some alloys.

Aluminum conduit is avoided, because when it gets wet and/or
attacked with alkali soil and pool chemicals and fertilizers it
quickly rots away to a jelly or oxide crumbles. Been there a few
times (when people tried homemade parts) and had to replace the whole
thing.

If you have corrosive or 'special' conditions, or underground, you
use gray PVC plastic conduit for the wiring.

-- Bruce --