Making an arbitrary angle in pipe


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.
Reply to
Don Foreman
Loading thread data ...
If you have time you can make bends the way I do on auto headers. Pick a 45, 90, or 180 bend, lay your straight sections out then just cut out the appropriate section from the bend you have. Weld it in, grind smooth and plate/paint as needed. With this trick you can make smooth bends that will drive folks nuts.
Reply to
Steve W.
I've use a street 45 elbow and a regular 45 elbow many times for all those odd angles between 90 and 180 degrees. I'm certain you can get all these angles with just these two parts if you don't mind the slight offset. From a mathemtical point of view, you get the mirror image also, so 90 to 270 degrees is covered. Assuming you're not after acute angles, where is the third 45 needed?
Karl
Reply to
Karl Townsend
Check with a muffler shop. They have machines that can bend it to the nth degree, and it comes out nice and finished so the wire can pass through it. Inexpensive, too.
Steve
Reply to
Steve B
Just get somebody with a hydraulic tubing bender to do it for you. A buddy of mine has the local dune buggy shop do his.
Reply to
Bob La Londe
No offset. Both pipes are in the same plane -- the outside of the house.
Reply to
Don Foreman
I did think of that. The 2" conduit used for outside feeds is considerably heavier than exhaust pipe, don't know if they could bend that or not.
Reply to
Don Foreman
There's a shop half a mile from here that does that. I priced one bend about 15 years ago. Yikes!
Reply to
Don Foreman
I like that idea! I was trying to avoid burning off zinc and needing to re-plate, but it would make a slick job of it.
Reply to
Don Foreman
Two things: Don't cost to ask, and it don't have to be perfect.
Steve
Reply to
Steve B
3 words: Hydraulic Pipe Bender
Horrible Fright has them to bend up to 3" pipe or rigid conduit for about $200.
This one is slightly more, but the 'air over hydraulic' is a big help:
The usual caveats about HF quality apply...
Carla
I love wearing low cut shirts cuz then when class gets boring, I can look down and admire my breasts. textsfromlastnight.com
Reply to
Carla Fong
Forget about metal conduit - use PVC and heat bend it as required. Gerry :-)} London, Canada
Reply to
Gerald Miller
I have been considering a combination of tubing bender and notcher to make some frames for canvas work, and some covered with corrugated profile roofing. Really not rocket surgery, and if you get the triangulation and cross bracing right, pretty sturdy.
Steve
Reply to
Steve B
If I'm reading the first part of this post correctly this "pipe" is a part of the 'service entry' system. The NEC and local codes have some very hard and fast requirements for the material used and the installation of same. PLEASE check with a local electrician, or your electrical inspector, for his advice before material is 'cut', 'bent', _'welded'_, etc. (most codes frown on PVC for service entry use)
Bending Rigid Metal Conduit is just like bending Galvanized Metal Pipe. Any electrical shop or pipe shop should be able to do the bending for you.
Bob (used-to-was electrician) rgentry at oz dot net
Reply to
Bob Gentry
... (most codes frown on PVC for service entry use)
Around here (NW of Boston) it's used almost exclusively. For residential anyhow. Bob
Reply to
Bob Engelhardt

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.