12 years ago
My neighbor is re-doing his electrical service feed because he wants
to increase capacity to 200 amps. As part of that, he wants to
re-route the outdoor conduit from meter to relocated mast. We found
that his roof pitch is 5 in 12 or 22.62 degrees. He wondered if I
could bend 2" pipe. The short answer is "not well".
I got to thinking about elbows. It's fairly obvious that any arbitrary
angle can be achieved in a given plane with four 90-deg elbows. We
wondered what could be done with 45 deg elbows. I played with Alibre
for a while. Turns out four 45's can't get it done ... but three 45's
can! They go a bit out of plane but not a lot and the two runs can be
coplanar as in up against the house. I was even able to get the
various rotation angles, as if such a thing might need to be
fabricated and welded a priori. I just did that to see if I could, and
how hard it might be to do with Alibre.
Three 30's, like the familiar 3-section flue elbows, might work even
better but I don't know that 30 deg elbows are available in 2". I
don't know that 45's are either, but it seems likely.