# bending a 90 using 45's



## jusme123 (Dec 27, 2010)

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)?


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## bobelectric (Feb 24, 2007)

Use the center bend mark on the bender.


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## HARRY304E (Sep 15, 2010)

jusme123 said:


> 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


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## jusme123 (Dec 27, 2010)

bobelectric said:


> Use the center bend mark on the bender.


huh ????


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## jusme123 (Dec 27, 2010)

HARRY304E said:


> 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


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## brian john (Mar 11, 2007)

jusme123 said:


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


That just about has it all, interpret.


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## mattsilkwood (Sep 21, 2008)

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


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## jusme123 (Dec 27, 2010)

brian john said:


> That just about has it all, interpret.


Just about, but again, not what I need.


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## RUSSIAN (Mar 4, 2008)

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


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## BBQ (Nov 16, 2010)

mattsilkwood said:


> 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.


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## Jlarson (Jun 28, 2009)

mattsilkwood said:


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





BBQ said:


> Same here, just go for it.


Me three


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## mattsilkwood (Sep 21, 2008)

BBQ said:


> Same here, just go for it.


 Truth be known it's probably quicker to.


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## bobelectric (Feb 24, 2007)

jusme123 said:


> huh ????[/quot
> 
> Dude,get a Benfield Bender Book. You can even get labels for your handle that has a quick reference to degree multipliers and accessory.


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## BuzzKill (Oct 27, 2008)

BBQ said:


> Same here, just go for it.


I thought you just sat in your truck and talk on the phone? :blink:


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## brian john (Mar 11, 2007)

mattsilkwood said:


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


I always used a folding rule. Still carry one, fiber glass for pointing or measuring in questionable locations.


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## 480sparky (Sep 20, 2007)

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








​


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## jusme123 (Dec 27, 2010)

bobelectric said:


> jusme123 said:
> 
> 
> > huh ????[/quot
> ...


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## brian john (Mar 11, 2007)

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


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## jusme123 (Dec 27, 2010)

480sparky said:


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


Yes it is what I am looking for


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## BBQ (Nov 16, 2010)

BuzzKill said:


> I thought you just sat in your truck and talk on the phone? :blink:


(Hangs head low) Yeah pretty much the case now. 

Once in a while I still use the tools.


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## mattsilkwood (Sep 21, 2008)

BBQ said:


> Once in a while I still use the tools.


 Gotta have something to throw at the guys to get their attention huh.:laughing:


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## 480sparky (Sep 20, 2007)

jusme123 said:


> Yes it is what I am looking for



Can't say I've ever seen the formula.


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## Rockyd (Apr 22, 2007)

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!


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## brian john (Mar 11, 2007)

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?


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## manchestersparky (Mar 25, 2007)

brian john said:


> I always used a folding rule. Still carry one, fiber glass for pointing or measuring in questionable locations.


I always had a folding rule in my pouch. I used to do the same exact thing Brian!


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## erics37 (May 7, 2009)

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.


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## jbfan (Jan 22, 2007)

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


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## brian john (Mar 11, 2007)

480sparky said:


> Can't say I've ever seen the formula.


Seems like it might be a test question?


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## brian john (Mar 11, 2007)

jbfan said:


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


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


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## BuzzKill (Oct 27, 2008)

brian john said:


> 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


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## erics37 (May 7, 2009)

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


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## brian john (Mar 11, 2007)

erics37 said:


> 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


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## jbfan (Jan 22, 2007)

brian john said:


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


 
Oh yes we do!:jester:
How do you think we all get along on this forum?

Wise asses, with some very helpful info thrown in!:thumbup:


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## erics37 (May 7, 2009)

brian john said:


> 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


:laughing::laughing:


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## Jlarson (Jun 28, 2009)

BBQ said:


> (Hangs head low) Yeah pretty much the case now.


That sucks 

I hate jobs like that and refuse to ever take an office position.


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## NolaTigaBait (Oct 19, 2008)

jbfan said:


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


Sometimes that is the easiest thing to do...but some anal electricians want to make it complicated.


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## 480sparky (Sep 20, 2007)

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.


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## Bkessler (Feb 14, 2007)

mattsilkwood said:


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


This is one that's not to tough to eyeball with a practice on a scrape piece, three 30's work too!










I did these one's in the pic just for easier pulling.


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## jusme123 (Dec 27, 2010)

erics37 said:


> 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.
> 
> ...


Thanks Eric!


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## 480sparky (Sep 20, 2007)

Bkessler said:


> .........I did these one's in the pic just for easier pulling.


And just how did it make pulling easier? :001_huh:


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## RePhase277 (Feb 5, 2008)

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.


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## jusme123 (Dec 27, 2010)

480sparky said:


> 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


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## jusme123 (Dec 27, 2010)

480sparky said:


> And just how did it make pulling easier? :001_huh:


larger radius 90's are easier to pull thru, that's the concept he is using


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## 480sparky (Sep 20, 2007)

jusme123 said:


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



Tell the plumber to move his freakin' pipe, then. :laughing:


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## brian john (Mar 11, 2007)

InPhase277 said:


> 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:


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## danickstr (Mar 21, 2010)

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.


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## ZZDoug (Apr 30, 2008)

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.


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## Jlarson (Jun 28, 2009)

ZZDoug said:


> 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.


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## frenchelectrican (Mar 15, 2007)

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


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## Southeast Power (Jan 18, 2009)

ZZDoug said:


> 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.



By the time someone screws around with bending wire or making a mock up piece, you could have all of these marks on the pipe and begin bending the conduit. 
If you have been running conduit for a couple of weeks or so, you can eyeball these measurements and not realize that you are running the calculations in your head.
Nice description ZZ. You have some fine teaching skills.


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## marmanson96 (Jan 14, 2010)

jbfan said:


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


That is NOT craftsmanship !!!


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## don_resqcapt19 (Jul 18, 2010)

jusme123 said:


> larger radius 90's are easier to pull thru, that's the concept he is using


 The pulling force formulas do not support that idea.


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## BBQ (Nov 16, 2010)

marmanson96 said:


> That is NOT craftsmanship !!!


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


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## NolaTigaBait (Oct 19, 2008)

BBQ said:


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


Where do people come up with this crap?


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## Bkessler (Feb 14, 2007)

480sparky said:


> And just how did it make pulling easier? :001_huh:


It just does, or at least in my brain it seems easier to pull and to get the fish tape through. Maybe it's magic.


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## Speedy Petey (Jan 10, 2007)

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.


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## open short (Oct 12, 2010)

ZZDoug said:


> 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.


d x 2.4 for round
d x 3 for square
d1 + d2 x 1.4 for rectangular


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## oldtimer (Jun 10, 2010)

open short said:


> d x 2.4 for round
> d x 3 for square
> d1 + d2 x 1.4 for rectangular


 O M G. Are we making this complicated or WHAT??


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## open short (Oct 12, 2010)

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


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## don_resqcapt19 (Jul 18, 2010)

Bkessler said:


> It just does, or at least in my brain it seems easier to pull and to get the fish tape through. Maybe it's magic.


 To me the long radius bends seem harder to pull ... the only real reason to use them is to reduce the sidewall pressure (crushing force) on the insulation when making a pull, or for cables that have a minimum bending radius larger than the the radius of a standard bend.


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## oldtimer (Jun 10, 2010)

open short said:


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



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


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## BBQ (Nov 16, 2010)

oldtimer said:


> O M G. Are we making this complicated or WHAT??


Not at all, this is me just trying to figure out a box offset.


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## running dummy (Mar 19, 2009)

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


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## George Stolz (Jan 22, 2009)

I use A squared plus B squared = C squared.

A is vertical
B is horizontal
C is diagonal


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## BBQ (Nov 16, 2010)

George Stolz said:


> I use A squared plus B squared = C squared.
> 
> A is vertical
> B is horizontal
> C is diagonal











:laughing:


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## mattsilkwood (Sep 21, 2008)

George Stolz said:


> I use A squared plus B squared = C squared.
> 
> A is vertical
> B is horizontal
> C is diagonal


 A sq + B sq / sq rt= c


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## brian john (Mar 11, 2007)

Pythagorean theorem.


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## guest (Feb 21, 2009)

don_resqcapt19 said:


> To me the long radius bends seem harder to pull ... the only real reason to use them is to reduce the sidewall pressure (crushing force) on the insulation when making a pull, or for cables that have a minimum bending radius larger than the the radius of a standard bend.


Hi Don, welcome to the loony bin in here...:laughing:


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## Bkessler (Feb 14, 2007)

don_resqcapt19 said:


> To me the long radius bends seem harder to pull ... the only real reason to use them is to reduce the sidewall pressure (crushing force) on the insulation when making a pull, or for cables that have a minimum bending radius larger than the the radius of a standard bend.


I beg to differ,


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## Jlarson (Jun 28, 2009)

marmanson96 said:


> That is NOT craftsmanship !!!





What are they teaching in apprenticeships and trade schools these days? 

If one of my guys was standing around crunching numbers (read: f'ing waste of time) when they could just mock it up or trying to make a perfect bend (yet another waste of time) when a coupling would have the job done already I might just have to yell.


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## jusme123 (Dec 27, 2010)

Jlarson said:


> What are they teaching in apprenticeships and trade schools these days?
> 
> If one of my guys was standing around crunching numbers (read: f'ing waste of time) when they could just mock it up or trying to make a perfect bend when a coupling (yet another wast of time) would have the job done already I might just have to yell.


...your going to 'mock up' a piece of four inch rigid conduit? Do you run much conduit?


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## Jlarson (Jun 28, 2009)

jusme123 said:


> ...your going to 'mock up' a piece of four inch rigid conduit? Do you run much conduit?


Yep, not just conduit either I back up out mechanics/fitters sometimes so doing large pipe is nothing new to me.


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## mattsilkwood (Sep 21, 2008)

Jlarson said:


> What are they teaching in apprenticeships and trade schools these days?
> 
> If one of my guys was standing around crunching numbers (read: f'ing waste of time) when they could just mock it up or trying to make a perfect bend when a coupling (yet another waste of time) would have the job done already I might just have to yell.


 I agree to a point. Using couplings where you don't need to is a pet peve of mine. Don't get me wrong, if the customer is paying for a Yugo then they don't get a Cadillac but most of the jobs I work aren't like that.
I think it should look as good as it works.


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## jusme123 (Dec 27, 2010)

don_resqcapt19 said:


> To me the long radius bends seem harder to pull ... the only real reason to use them is to *reduce the sidewall pressure (crushing force)* on the insulation when making a pull, or for cables that have a minimum bending radius larger than the the radius of a standard bend.


...would that reduce the friction:yes:


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## Jlarson (Jun 28, 2009)

mattsilkwood said:


> Using couplings where you don't need to is a pet peve of mine.


Well if the guys are using couplings everywhere I'm yelling then too :laughing:


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## mattsilkwood (Sep 21, 2008)

Jlarson said:


> Well if the guys are using couplings everywhere I'm yelling then too :laughing:


 You yell a lot.:laughing:


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## jusme123 (Dec 27, 2010)

Jlarson said:


> What are they teaching in apprenticeships and trade schools these days?
> 
> If one of my guys was standing around crunching numbers (read: f'ing waste of time) when they could just mock it up or trying to make a perfect bend when a coupling (yet another waste of time) would have the job done already I might just have to yell.


4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how you would do this.


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## Jlarson (Jun 28, 2009)

mattsilkwood said:


> You yell a lot.


:laughing:


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## mattsilkwood (Sep 21, 2008)

jusme123 said:


> 4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how you would do this.


 You're gonna need an Erickson.:whistling2:


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## Jlarson (Jun 28, 2009)

jusme123 said:


> 4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how you would do this.


Once I had my centers for the 45's I'd bend it then cut and thread the one side as necessary to fit up to the run. If it's a pre-bend job I'd just measure out the pieces I need to go between the 45's.


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## Jlarson (Jun 28, 2009)

mattsilkwood said:


> You're gonna need an Erickson.:whistling2:


Or use compression connectors.


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## 480sparky (Sep 20, 2007)

jusme123 said:


> 4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how you would do this.



Off the cuff, I'd say a 90° bend will clear the 4" pipe in the corner. :whistling2:


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## McClary’s Electrical (Feb 21, 2009)

480sparky said:


> Off the cuff, I'd say a 90° bend will clear the 4" pipe in the corner. :whistling2:


 
X2:thumbup:


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## Jlarson (Jun 28, 2009)

480sparky said:


> Off the cuff, I'd say a 90° bend will clear the 4" pipe in the corner. :whistling2:


Depending on how the drain is supported, and how your conduit is supported, maybe it would clear maybe not.


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## BBQ (Nov 16, 2010)

jusme123 said:


> 4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how you would do this.



I would take my tape measure and place it where I want the pipe and note the measurement, then I would make the pipe.


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## 480sparky (Sep 20, 2007)

Jlarson said:


> Depending on how the drain is supported, and how your conduit is supported, maybe it would clear maybe not.



I can't think of any way to support your 4" rigid that would _reduce _the space behind it in the corner.


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## Jlarson (Jun 28, 2009)

480sparky said:


> I can't think of any way to support your 4" rigid that would _reduce _the space behind it in the corner.


What if the pipe in the corner isn't right in the corner, might me held off on strut, angle iron w/u-bolts or whatever. I've done that before with process pipe.


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## bobelectric (Feb 24, 2007)

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


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## brian john (Mar 11, 2007)

Heck..go with Greenfield.


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## Jlarson (Jun 28, 2009)

brian john said:


> 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:


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## BBQ (Nov 16, 2010)

Jlarson said:


> 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:


Don't lie, electricity will never work when run all in greenfield.:no:


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## bobelectric (Feb 24, 2007)

Let's go see what the boys over at Mike Holt.com told him!​


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## Jlarson (Jun 28, 2009)

BBQ said:


> Don't lie, electricity will never work when run all in greenfield.


:laughing::laughing::laughing:


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## erics37 (May 7, 2009)

Jesus, didn't I answer this f**king thing like 24 hours ago?



erics37 said:


> 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.
> 
> ...


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## jusme123 (Dec 27, 2010)

bobelectric said:


> Let's go see what the boys over at Mike Holt.com told him!​


:jester::jester::thumbsup::jester::jester: because obviously you don't know the formula! LOL


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## jusme123 (Dec 27, 2010)

Jlarson said:


> Or use compression connectors.


 couplings join, connectors are for boxes


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## Jlarson (Jun 28, 2009)

jusme123 said:


> couplings join, connectors are for boxes


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## ZZDoug (Apr 30, 2008)

erics37 said:


> Jesus, didn't I answer this f**king thing like 24 hours ago?


No, not exactly. Using the obstruction diameter x 2.4 would be pretty close in most cases, but as others have said, it also depends on how it is supported etc. In other words, how far out from the corner does your conduit need to be to clear the obstruction. That's the actual and only measurement you need to use, the obstruction diameter by itself doesn't necessarily tell you that. But your method is close.

As for those of you who cant or don't want to do simple math, I would have the conduit bent and be hanging it by the time you finished fooling around with some type of "mock up". But hey, if you want to be a hack instead of a craftsman, feel free.

To Don, I have run a lot of conduit over the years for communications cables where the engineers required minimum 24 inch radius bends. Its a lot more expensive and you could argue that it's overkill, but the reason is less pulling force required so therefore less potential damage to the wiring. There is a reason the NEC requires using a minimum radius bend for given conduit sizes.


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## jusme123 (Dec 27, 2010)

erics37 said:


> 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.*
> 
> ...


This is the formula that I used and it worked out PERFECTLY, thanks Eric!!


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## BBQ (Nov 16, 2010)

Duplicate post


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## BBQ (Nov 16, 2010)

ZZDoug said:


> As for those of you who cant or don't want to do simple math, I would have the conduit bent and be hanging it by the time you finished fooling around with some type of "mock up". *But hey, if you want to be a hack instead of a craftsman, feel free.*


I will get it done in less time and it will look good. But hey, if you want to be a prick you are doing well.



> To Don, I have run a lot of conduit over the years for communications cables where the engineers required minimum 24 inch radius bends. Its a lot more expensive and you could argue that it's overkill, *but the reason is less pulling force required *so therefore less potential damage to the wiring. There is a reason the NEC requires using a minimum radius bend for given conduit sizes.


You are 100% wrong about the pulling tension.

The reason for large radius sweeps is sidewall pressure and it can be proven using simple math.


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## Jlarson (Jun 28, 2009)

ZZDoug said:


> But hey, if you want to be a hack instead of a craftsman, feel free.












Guess we aren't craftsmen guys :lol: :lol:


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## BBQ (Nov 16, 2010)

If anyone is interested in the real reason large radius sweeps are used.

http://ecmweb.com/mag/electric_simple_calculations_cable/

http://www.electrician2.com/calculators/ductwirepull.htm


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## BBQ (Nov 16, 2010)

jusme123 said:


> ...would that reduce the friction:yes:


Nope it does not, as now there is a longer area of friction.

Follow the links.


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## HARRY304E (Sep 15, 2010)

BBQ said:


> I will get it done in less time and it will look good. But hey, if you want to be a prick you are doing well..


He 's trying to be as good as you:laughing::laughing:


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## Jlarson (Jun 28, 2009)

HARRY304E said:


> He 's trying to be as good as you


:w00t: :laughing:


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## BBQ (Nov 16, 2010)

HARRY304E said:


> He 's trying to be as good as you.


Everyone needs goals.


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## HARRY304E (Sep 15, 2010)

BBQ said:


> Everyone needs goals.


 Set them high:thumbsup:


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## leland (Dec 28, 2007)

jusme123 said:


> 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)?



You are kidding, right?:whistling2:


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## 480sparky (Sep 20, 2007)

leland said:


> You are kidding, right?:whistling2:



Naaa. We just thought we'd babble on for 6 pages just for shîts and giggles.


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## BBQ (Nov 16, 2010)

480sparky said:


> Naaa. We just thought we'd babble on for 6 pages just for shîts and giggles.



Like that would be any different than normal ...... myself included. :laughing:


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## RePhase277 (Feb 5, 2008)

OK, so I did the math and made some sketches, and it is NOT the same as a 45-45 offset. So ZZ was right. So, for a round object tight in the corner, the formula would be 

*d x 2.8 = distance between bends*

where d is the diameter of the object. Yes, 2.8. Not 1.4, or 2.4, but 2.8. For objects not exactly in the corner, you have to figure as if the diameter were increased to that distance.


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## Rockyd (Apr 22, 2007)

InPhase277 said:


> OK, so I did the math and made some sketches, and it is NOT the same as a 45-45 offset. So ZZ was right. So, for a round object tight in the corner, the formula would be
> 
> *d x 2.8 = distance between bends*
> 
> where d is the diameter of the object. Yes, 2.8. Not 1.4, or 2.4, but 2.8. For objects not exactly in the corner, you have to figure as if the diameter were increased to that distance.


?

I was right way back in the thread when I said D x 3.


Thinking that 2.8 gets you to the center of the pipe, I gave some consideration to the fact that the pipe had a diameter. Anyways, I'd have bent it already and moved on, got to get done in a timely fashion!

277 yours makes the most sense so far on this thread....


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## RePhase277 (Feb 5, 2008)

Rockyd said:


> ?
> 
> I was right way back in the thread when I said D x 3.
> 
> Thinking that 2.8 gets you to the center of the pipe, I gave some consideration to the fact that the pipe had a diameter. Anyways, I'd have bent it already and moved on, got to get done in a timely fashion!


True dat! I didn't have anything better to do, and never having had to bend such a beast, I sat down and made a pic and did the math. But it is one to file away as an addition to the Ugly's book.


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## danickstr (Mar 21, 2010)

zz is only right if you look at it his way. if you use the distance you want to be from the wall, and take that times 1.4, it will work that way as well. Measure from the front of the pipe, that eliminates the radius variability issue.


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## jusme123 (Dec 27, 2010)

....................


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## Rockyd (Apr 22, 2007)

jusme123 said:


> ....................


What? 

You thought that no one would respond???

That poor pipe has been studied, calculated, conceptualized, realized, upsized, downsized, messmerized, confounded, infuriated, daunted, been flaunted, considered and dithered, and measured till the numbers wore off of Fat Maxes and 6' folding rules alike.

If the S.O.B. is not in by the end of the day, you, and 116 other posters are down the road for lack of production....now just bend the 3/4" piece of E.M.T. and lets go!:laughing:


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## manchestersparky (Mar 25, 2007)

116 posts on how to make a simple flippin bend 

I now know why electricians drink !


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## oldtimer (Jun 10, 2010)

manchestersparky said:


> 116 posts on how to make a simple flippin bend
> 
> I now know why electricians drink !





THEY DO ???:laughing:


:drink::drink::drink: Again HAPPY NEW YEAR


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## jusme123 (Dec 27, 2010)

leland said:


> You are kidding, right?:whistling2:


Penny for your thoughts or keep your 2 cents
4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner, from the corner to the edge of the drain line there is a 6" space. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how* you* would do this.


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## BBQ (Nov 16, 2010)

jusme123 said:


> Penny for your thoughts or keep your 2 cents
> 4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner, from the corner to the edge of the drain line there is a 6" space. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how* you* would do this.



Are you threading a needle or just running pipe?

If for some reason you have to 'nail it' the formulas are a great way to go.

If you just have to miss the obstruction and don't care if you miss it by 1/8" or 2" then you just do it using a tape measure and your experience. 

I would place my tape where I wanted the pipe to be and that would give me the measurement between the 45s, after that it does not matter which mark on the bender you use as long as it is the same mark on each bend and you do not turn the pipe around.


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## jusme123 (Dec 27, 2010)

BBQ said:


> Are you threading a needle or just running pipe?
> 
> *If for some reason you have to 'nail it' the formulas are a great way to go.
> *
> ...


...formulas are the only way to go, you nail it every time (its larger size conduit not 3/4"). I know how to bend pipe, and I know I could have easily just made two 45's without regard to how far out it was from object, but I do not remember the formula and just asking if anyone does. The formula {D1 + D2 * 1.4 = distance between bends} worked ( left wall to outer pipe edge D1, right wall to outer pipe edge D2)


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## jusme123 (Dec 27, 2010)

Thanks for all the responses!!


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## Mike in Canada (Jun 27, 2010)

jusme123 said:


> Penny for your thoughts or keep your 2 cents
> 4" rigid conduit ends 4' from a wall corner and there is a 4" drain line in the corner, from the corner to the edge of the drain line there is a 6" space. Only way around corner is to use two 45 degree bends and go 'in front' of the 4" drain. Now, explain exactly how* you* would do this.


 A 90 degree bend in 4" conduit will leave you with more than enough space in the corner to avoid a 4" drain line, so I would use a 90 degree bend.

If it was 1/2" conduit then I'd eye-ball it, and if I was off a hair then I'd cut it and put a coupling in between the 45's.


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## knowshorts (Jan 9, 2009)

I got a headache.


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## BBQ (Nov 16, 2010)

jusme123 said:


> ...formulas are the only way to go, you nail it every time (its larger size conduit not 3/4").


No they are not the way to go every time, if that is how you like to do it that is fine.

But many of us run 4" pipe quite well without using formulas for every bend.

To me a person that needs to use formulas for every bend is inexperienced and slow with production.


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## jusme123 (Dec 27, 2010)

BBQ said:


> No they are not the way to go every time, if that is how you like to do it that is fine.
> 
> But many of us run 4" pipe quite well without using formulas for every bend.
> 
> To me a person that needs to use formulas for every bend is inexperienced and slow with production.


...the use of benders is based off formulas, keep stirring the pot :jester:


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## jusme123 (Dec 27, 2010)

Mike in Canada said:


> A 90 degree bend in 4" conduit will leave you with more than enough space in the corner to avoid a 4" drain line, so I would use a 90 degree bend.
> 
> If it was 1/2" conduit then I'd eye-ball it, and if I was off a hair then I'd cut it and put a coupling in between the 45's.


...read post #124 with particular attention to where 6" is stated


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## mattsilkwood (Sep 21, 2008)

jusme123 said:


> ...the use of benders is based off formulas,


 Then you've never seen an old timer run a bender.


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## 480sparky (Sep 20, 2007)

jusme123 said:


> ...the use of benders is based off formulas, keep stirring the pot :jester:



I just remember the take-ups. I have yet to bend a 3- or 4-bend saddle using 'the formula'.


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## jusme123 (Dec 27, 2010)

480sparky said:


> *I just remember the take-ups*. I have yet to bend a 3- or 4-bend saddle using 'the formula'.


whatever works for you


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## Big John (May 23, 2010)

mattsilkwood said:


> Then you've never seen an old timer run a bender.


 Ain't that the truth! Met an Irish sparky once who hardly even touched a tape measure. He could eyeball damn near any bend and it'd be closer than a lot of guys would get trying to calculate. It was nuts!

-John


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## BBQ (Nov 16, 2010)

jusme123 said:


> ...the use of benders is based off formulas, keep stirring the pot :jester:


Holy crap Batman you are really stuck in one mode aren't you? :laughing::laughing:

Yes formulas can be useful and without a doubt are sometimes needed.

But not every time, do you forget everything each time you make a bend? :blink::laughing:


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## brian john (Mar 11, 2007)

Guys like this cost owners money and therefore are candidates for a bench warming project...

If you have a tight fit..OK
Multiple runs FOR SURE.
Single run lay it and leave or else you are wasting time and money.


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## TOOL_5150 (Aug 27, 2007)

BBQ said:


> To me a person that needs to use formulas for every bend is inexperienced and slow with production.


Yes. the guy I work with was green when he started.. i taught him how to bend pipe without formulas, and now he can bend just about anything, and yes it does look good, - without having to get out a protractor and all that crap. 

~Matt


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## jusme123 (Dec 27, 2010)

TOOL_5150 said:


> Yes. the guy I work with was green when he started.. i taught him how to bend pipe without formulas, and now he can bend just about anything, and yes it does look good, - without having to get out a protractor and all that crap.
> 
> ~Matt


...so if he needs a 36" 90 degree bend he just eyeballs huh :laughing:


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## brian john (Mar 11, 2007)

jusme123 said:


> ...so if he needs a 36" 90 degree bend he just eyeballs huh :laughing:


I can't but some of the pipe artist I have worked with over the years can, once they make the first setup they rock and roll on the others.


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## BBQ (Nov 16, 2010)

jusme123 said:


> ...so if he needs a 36" 90 degree bend he just eyeballs huh :laughing:


Are you trying to call the bender deduction a 'formula'? :laughing:


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## Jlarson (Jun 28, 2009)

BBQ said:


> Are you trying to call the bender deduction a 'formula'?



:laughing::laughing::laughing:


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## 480sparky (Sep 20, 2007)

BBQ said:


> Are you trying to call the bender deduction a 'formula'? :laughing:



Well, yeah.

DL+TU=WOTFSOPYPYM.

Where TU = Take Up (the deduction for the size of bender/pipe you're using).

DL= Developed length.

WOTFSOPYPYM=Where on the freakin' stick of pipe you put your mark.

:laughing:


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## jusme123 (Dec 27, 2010)

BBQ said:


> Are you trying to call the bender deduction a 'formula'? :laughing:





Jlarson said:


> :laughing::laughing::laughing:


Bob, it's a mathematical result based off formulas.


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## mattsilkwood (Sep 21, 2008)

I was poking through the Android market today and they have an app for that. It's called Conduit Runner, It's got the compound 90, rolling offsets, saddles and conduit fill.


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## jusme123 (Dec 27, 2010)

mattsilkwood said:


> I was poking through the Android market today and they have an app for that. It's called Conduit Runner, It's got the compound 90, rolling offsets, saddles and conduit fill.


thats pretty cool, it also has much more than that for electrical


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## mattsilkwood (Sep 21, 2008)

jusme123 said:


> thats pretty cool, it also has much more than that for electrical


 If you like that one check out Elec Wiring Pro. It's got some usefull stuff too.


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## rdr (Oct 25, 2009)

I was googling trying to see if there was a way to figure where to mark your bends if you needed it a specific length not necessarily a specific size obstruction. I ran across a situation that needed one today. I tried one with the back bend at the 90 length and bending on the star. I couldn't remember if I ever did know how to figure it but figured it was worth a shot. Jacked that one up horribly (came out 2 inches or so too short) I just ended up bending another one too long and cutting it off. I think it turned out OK. No sharpie marks on my pipe either!!:jester:


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## Control Freak (Mar 8, 2008)

Just hold up your rule across the obstruction from wall to wall. That's where your bends need to be on the pipe. Just use the rim notch not the star. The star is back of 90 not Center of bend for a 45. That's the run notch sir.


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## McClary’s Electrical (Feb 21, 2009)

rdr said:


> I was googling trying to see if there was a way to figure where to mark your bends if you needed it a specific length not necessarily a specific size obstruction. I ran across a situation that needed one today. I tried one with the back bend at the 90 length and bending on the star. I couldn't remember if I ever did know how to figure it but figured it was worth a shot. Jacked that one up horribly (came out 2 inches or so too short) I just ended up bending another one too long and cutting it off. I think it turned out OK. No sharpie marks on my pipe either!!:jester:
> 
> View attachment 10515


 
You didn't quite get it 45, it hanging off the ceiling and the wall.


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## rdr (Oct 25, 2009)

mcclary's electrical said:


> You didn't quite get it 45, it hanging off the ceiling and the wall.


It's gonna go down the wall to an FS box that isn't yet nailed up and the straps aren't even tightened down. Just sort of started the tapcons to check it out right at quitting time. That and finishing those 2 walls are first on the agenda tomorrow.


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## user8640521 (Jan 17, 2009)

christ. this thread is a year old. i hit reply before i looked.

there is eight freaking pages from a year ago, telling a guy how to 
bend TWO 45 degree bends, so that it will fit.


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## 360max (Jun 10, 2011)

FulThrotl said:


> christ. this thread is a year old. i hit reply before i looked.
> 
> there is eight freaking pages from a year ago, telling a guy how to
> bend TWO 45 degree bends, so that it will fit.


........................


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## guest (Feb 21, 2009)

FulThrotl said:


> christ. this thread is a year old. i hit reply before i looked.
> 
> there is eight freaking pages from a year ago, telling a guy how to
> bend TWO 45 degree bends, so that it will fit.


You're new here, aren't you? :laughing::laughing::laughing::laughing:

This is business as usual in this nuthatch. :laughing::laughing:


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## rdr (Oct 25, 2009)

mcclary's electrical said:


> You didn't quite get it 45, it hanging off the ceiling and the wall.


No faulty bending. Here's the real source of the problem. Level flat on the deck.


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## CFL (Jan 28, 2009)

Jlarson said:


> Guess we aren't craftsmen guys :lol: :lol:


I think you're a hack who is part of the "cool" click online. I think you have some good input sometimes, but most of the time sound like ass kissing follower. You are one that says someone is wasting time because they are doing something beyond your abilities. I work with alot of dumbasses with the same attitude. That attitude is how they got to where they're at and those with more skills will always be ridiculed because they are a threat. I already know what your response will be to this post because it is the same as any other.


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## CFL (Jan 28, 2009)

I just read through every page in this thread and replied without realizing how old it was. Oh well, I got that off my chest.

Jlarson, just to be fair, you're not the only one I feel this way about. 

I know, you don't care.


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