# Need help making a rolling offset



## william1978 (Sep 21, 2008)

Do you know how large of an offset you will be trying to make?


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## RePhase277 (Feb 5, 2008)

If you measure the two directions you need to make the offset in, and then mark them from the corner of something square, the distance between the marks diagonally will be the depth of the offset you need to bend.

In other words, if you need to go over 4" and back 3", you need an offset 5" deep. This is like the two measurements for the legs of a right triangle, and the hypotenuse is the depth of the offset.

Mathematically, square each measurement, add them together, then take the square root. That is the offset you need.


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## user4818 (Jan 15, 2009)

InPhase277 said:


> Mathematically, square each measurement, add them together, then take the square root. That is the offset you need.


Yup, basic geometry. How many electricians have taken geometry though? :001_huh:


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## steadypimpin (Jun 8, 2009)

I don't know the measurements yet, I will tomorrow. So basically I just take my measurement diagonally and make that size offset?


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## Shaffer87 (Feb 11, 2009)

Use your tape to measure diagonally as needed for your roll? :laughing: Depending on the symmetry of your rack you can bend all of them at the same time this is usually easier. Just bend one and make sure it fits if this is the case. If not measure and bend one by one.

Edit
Angles = Multiplier
10 = 5.76
22.5 = 2.6 (2.5)
30 = 2.0
45 = 1.41 (1.5)
60 = 1.15

Typically all you ever need is 22, 30 and 45.


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## RePhase277 (Feb 5, 2008)

steadypimpin said:


> I don't know the measurements yet, I will tomorrow. So basically I just take my measurement diagonally and make that size offset?


Yeah, diagonally across the square of the two measurements. Think about it like this: say the offset needs to go 4 inches to the right, and 3 inches back. Find a square table and mark 4" from the corner on one side, and 3" from that corner on the perpendicular side. The distance between marks is the depth you need.


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## user4818 (Jan 15, 2009)

A perfect 3, 4, 5 triangle.


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## MDShunk (Jan 7, 2007)

I use a framing square. Lay it on the floor. If your offset is 5-1/2" in one direction and 9" in the other direction, look at those two numbers on the square. Measure diagonally between those two numbers, accounting for pipe diameter if need be (depending on how you measured originally). That's the depth of the offset you need to bend. Basically what inphase277 said.


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## user4818 (Jan 15, 2009)

MDShunk said:


> I use a framing square.


I use the Pythagorean theorem. But only because I keep a calculator and not a framing square in my tool kit.


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## MDShunk (Jan 7, 2007)

Peter D said:


> I use the Pythagorean theorem. But only because I keep a calculator and not a framing square in my tool kit.


Measuring along two lines in a VCT floor and making tick marks with a pencil works too. Along sawcuts in a slab. Whatever it takes.


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## Mike_586 (Mar 24, 2009)

I just finished a job doing a bunch of 3" for parallel runs of 350mcm. I used (since I have one) a laser level to get the measurements I needed, though using a framers square or Pythagorean theorem would have given the same results. Though the laser is a lot easier


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## steelersman (Mar 15, 2009)

Peter D said:


> Yup, basic geometry. How many electricians have taken geometry though? :001_huh:


I actually took Geometry I in 9th grade.


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## user4818 (Jan 15, 2009)

steelersman said:


> I actually took Geometry I in 9th grade.


I think I took it in 10th grade. I didn't do so well in it, though. But then I aced trig the next year. :thumbsup:


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## paul d. (Jul 13, 2008)

Mike_586 said:


> I just finished a job doing a bunch of 3" for parallel runs of 350mcm. I used (since I have one) a laser level to get the measurements I needed, though using a framers square or Pythagorean theorem would have given the same results. Though the laser is a lot easier


 laser does work great!! but dont leave it laying on the floor.... when scizzor lifts are running around. :whistling2:


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## steelersman (Mar 15, 2009)

Peter D said:


> I think I took it in 10th grade. I didn't do so well in it, though. But then I aced trig the next year. :thumbsup:


I did much better in Geometry than Trig although I don't remember much of any of it other than basic stuff.


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## steelersman (Mar 15, 2009)

Peter D said:


> I use the Pythagorean theorem. But only because I keep a calculator and not a framing square in my tool kit.


That's cause you're a tool!


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## 480sparky (Sep 20, 2007)

steelersman said:


> That's cause you're a tool!


 
Hey!... HEY!.... HEY!


Peter is *NOT* a tool. He is a _*HACK*_.















































*I* am a tool!


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## steelersman (Mar 15, 2009)

Ahem....sorry. :blink:


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## user4818 (Jan 15, 2009)

steelersman said:


> That's cause you're a tool!


Thankfully Ken straightened you out, but man, that hurt!


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## 220/221 (Sep 25, 2007)

Flex.


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## Mike_586 (Mar 24, 2009)

paul d. said:


> laser does work great!! but dont leave it laying on the floor.... when scizzor lifts are running around. :whistling2:


:laughing: 

Seen lots of stuff get run over... usually a high percentage of our boxes and stubbed pipes.

I was actually using a torpedo level...










My problem was sometimes forgetting the level stuck to the pipe or a rack :jester:


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## paul d. (Jul 13, 2008)

220/221 said:


> Flex.


 flex ? FLEX!!!!!?????


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## user4818 (Jan 15, 2009)

220/221 said:


> Flex.


That's a good option. :thumbup:


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## william1978 (Sep 21, 2008)

220/221 said:


> Flex.


 I see guys use flex that can't bend conduit. It sure looks funny when every bend is in flex.:laughing:


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## drsparky (Nov 13, 2008)

How can you be an electrician without math skills? Everyone in this field should be able to do simple Trig, Geometry, and Algebra.


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## william1978 (Sep 21, 2008)

drsparky said:


> How can you be an electrician without math skills? Everyone in this field should be able to do simple Trig, Geometry, and Algebra.


 Thats a right.:thumbsup:


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## user4818 (Jan 15, 2009)

drsparky said:


> How can you be an electrician without math skills? Everyone in this field should be able to do simple Trig, Geometry, and Algebra.



Many electricians don't even understand grounding, bonding and basic theory, let alone math skills. :blink:


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## 220/221 (Sep 25, 2007)

> flex ? Flex!!!!!?????


 
ok.......nm?


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## william1978 (Sep 21, 2008)

220/221 said:


> ok.......nm?


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## 480sparky (Sep 20, 2007)

william1978 said:


> I see guys use flex that can't bend conduit.....


I see more guys who can't bend conduit use flex, myself. :whistling2:


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## rlc3854 (Dec 30, 2007)

paul d. said:


> laser does work great!! but dont leave it laying on the floor.... when scizzor lifts are running around. :whistling2:


 
SO your the guy!:hammer::cursing:


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## oldman (Mar 30, 2007)

Peter D said:


> Many electricians don't even understand grounding, bonding and basic theory, let alone math skills. :blink:


heck, if more knew a lick of math, we'd raise our prices:laughing:


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## user4818 (Jan 15, 2009)

oldman said:


> heck, if more knew a lick of math, we'd raise our prices:laughing:


Having business math skills over rides the need for trade math skills. :thumbup:


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## william1978 (Sep 21, 2008)

480sparky said:


> I see more guys who can't bend conduit use flex, myself. :whistling2:


  and its a shame.


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## user4818 (Jan 15, 2009)

480sparky said:


> I see more guys who can't bend conduit use flex, myself. :whistling2:


Who might that be? :whistling2:


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## vinster888 (May 3, 2009)

math skills? mechanical skills? in the age of sponge off the government? thats a sensitive issue 'round here.


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## erics37 (May 7, 2009)

I majored in Math in college (till I dropped out ). I love it. Everyone else on the job is sitting there eyeballing conduit or doing some weird "tape measure" deal to approximate offsets. I'm proud of my math skillz, and I have a calculator screwed to the inside of my toolbox lid, along with a couple conduit "cheat sheets" (offset multiplier tables and such). In my first time I was assigned to a big industrial job and for 2 months straight they put with me a journeyman doing nothing but bending, cutting, and threading rigid pipe. Guys would come in with their sketches and measurements and we'd just sit there and bend all day. Concentrics, parallel offsets, everything. It was my favorite part of the job.

The first time someone gave me a hand bender for EMT I was like "What the hell is this thing?"

(Side note: I have since decided that a hand bender is my blunt weapon of choice in the event of a zombie invasion. Heavy duty and easy to swing.)


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## steadypimpin (Jun 8, 2009)

I know the math stuff. I just wanted to see if there was an easier method to the rolling offset. I just used a way I always do & it turned out great. I had the pipe that I had been running stuck out off the rack about 2 feet and I stuck another stick of pipe on the rack I had to roll onto. I made them even so I just took my tape and measured across from one pipe to the other. It looks awesome after I finished. I need to start doing the mathematical way next time which I'm sure I'll be able to because I have a long way to go still. I'll take some pics tomorrow and post em up for you guys and you can give me your feedback. The rolling offsets ended up being about 55 inches. I used 60 degree angle bends for the offsets because I wanted to get it all on one stick.


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