Use the center bend mark on the bender.

 

huh ????

 

anyone remember the formula for bending a 90 degree bend using (2) 45 degree bends (to get around an obstacle in the corner of a wall)?

Take a look at this click it is loaded with good info..

http://www.mikeholt.com/documents/freestuff/BendingRoundRaceways.pdf

 

...does not have what I am asking for, but thanks

 

I've found that the easiest way for me is just lay a piece of scrap up there and you can get your centers.

 

Same here, just go for it.

 

its called a compound 90, but I cant remember the formula. but you can probably google compound 90

 

I think he's looking for a formula to bend this:

​

 

Yes it is what I am looking for

 

http://hubpages.com/hub/EMT-Electrical-Conduit-Pipe-Bending-the-Math-Behind-a-Conduit-Bending-Guide....................

 

If it's a pipe you're going around I'd use a multipier of 3 times the diameter, for my hypotenuse. Maybe double the size of the diameter (for the legs) to get your point to point measure for the hypotenuse measurement. That's my story, and am sticking to it

I think that'll work. If it's that damn important, lay it out on the floor, then follow whatever you come up with that works. It's only pipe!

 

I have no bet conduit in years, but I use to bend my first 45 measure center to center make that mark as my center point and bend a second 45.


While I never thought about it why is it any different the bending a 2-45 offset? with the second bend flipped?

 

exactly, back to back 45's

 

For a round obstruction: obstruction diameter x 2.4 = distance between bending marks.

For a a rectangular or square obstruction, with sides D1 and D2, then (D1 + D2) x 1.4 = distance between bending marks.

Make both bends with the bender head facing in the same direction for each.

If you're trying to preposition the bend a set distance from the end of the pipe it's a bit more complicated. Probably easier to do it hack style and bend the compound 90 wherever and then cut the stub to length.

I pulled this info out of my trusty ol' Richard A. Cox Electricians Guide to Conduit Bending.

 

Thanks Eric!

 

Make two bends and put a coupling in the middle!!

 

Everybody likes a little ass, no one likes a wise ass.....:laughing:

 

I've done quite a bit of conduit work, but it is worth noting that I have bent a compound 90 exactly ONE time. And it was part of the electrician contest I competed in a few months ago. I royally f**ked it up too

 

I've done quite a bit of conduit work, but it is worth noting that I have bent a compound 90 exactly ONE time. And it was part of the electrician contest I competed in a few months ago. I royally f**ked it up too

You did not need to tell us that,,,,,we figured that out from the first sentence.:whistling2:

I am on a roll tonight......

and exceed 9G's

 

I'd just put two 45s in a stick and try it... see how far it's off and bend a second one if needed. Done.

 

...what if its 4" rigid, cost does come into play

 

This bend would be exactly the same as a 45-45 offset, except that one of the bends is the wrong way. Figure it just the same as an offset, take-up and all. Use a multiplier of 1.4 to figure distance between bends.

 

And I THINK this was said 5 different ways 6 times, BUT you nailed it.:thumbsup:

 

1.4 is the right multiplier.
So if your corner starts 6 inches from the other wall, subtract 6 inches plus your take-up based on conduit size like a 90, then take 6 x 1.4 =8 and a half inches (minus take-up), then make your other 45 bend and it should work. I guess it was said 7 times now but hey what the heck.

 

You are all wrong. It is not the same as a 45 degree offset, nor is it a 1.4 multiplier. You were the guys in apprentice class that thought the trig they were trying to teach you was useless, but you were wrong then too. Bending conduit is all about triangles. You can make the most complicated bends and layouts by simplifying down to triangles and finding the length of sides or angles. If you understand this you will know the biggest and most profound secret about conduit bending. I use the word secret because so few do get this.

Look at the diagram, and like all conduit bending break it down into simple triangles. For example, your conduit and the two walls will form a triangle. To find the length of the conduit (distance between bends) you need to know the length of the wall from the corner to each bend (they will each be the same). This is the green line.
Generally, when you use a bend like this you are trying to clear an object in the corner, and this is what the OP was asking about. In the diagram this distance would be from the corner out to the outside edge of the red round object, the orange or yellow line. Lets call this distance X. So X would be a line from the corner out to your conduit, thus dividing your triangle into two smaller ones. Anyway with a little math, either trig or geometry, you can see that the wall length (the green line) equals 1.415x and with the Pythagorean theorem or simple trig or simple logic you can see that the length of the conduit (distance between bends) is 2X. However this is theory and in actual practice you want the conduit to slightly clear the object, so you actually want your bends to be a little further apart. So for smaller conduit I use 2.25X and for larger conduit I use 2.5X. And there you are.

 

You are all wrong..........And there you are.

And by the time you're done measuring and crunching numbers the guys that just mock it up with a piece of scrap whatever or a folding rule are all done and moving on.

 

For me the fastest way is take a scrap 10mm² { 8 AWG } soild copper conductor and make a quick forum of pattern and transfer over to the conduit and be done with it.

Many time time is money .,,,
so ya have to figure out real quick which way you will do.

Merci.
Marc

 

Make two bends and put a coupling in the middle!!

That is NOT craftsmanship !!!

 

Yeah, using couplings as they are intended to be used is hack for sure.:laughing:

 

I would measure the 45deg part distance you need, bend a 45 at the starting point one way, mark the length of the 45deg part, then bend the other 45 the other way.

Make sense?
I agree, I have never seen a formula for this.

 

the question was asked...just an answer.now go back to sleep.

 

:sleeping::sleeping::sleeping::sleeping:

 

I know we have been beating this topic to death but here is a good website for other bending questions. I don't believe they cover this question specifically though ha ha
http://www.porcupinepress.com/_bending/ConduitBending.htm

 

I use A squared plus B squared = C squared.

A is vertical
B is horizontal
C is diagonal

 

:laughing:

 

Pythagorean theorem.

 

Then you maybe could use an LL, an LB and a LR !

 

Heck..go with Greenfield.

 

I should have taken pictures of the pump/equipment room I rewired in flex. I was given a sketch of the room on a napkin and was supposed to do the work with no site visit. So a few rolls of flex and a lot of one hole straps later I got it done. No need for any math either. :laughing:

 

Let's go see what the boys over at Mike Holt.com told him!
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:jester::jester::thumbsup::jester::jester: because obviously you don't know the formula! LOL