# Conduit bending question



## Dizzykidd (Aug 3, 2016)

I don't know what I am doing wrong, but if I try to bend let's say a 30 degree bend it comes out about an inch bigger. The same thing happens with my 90 degree bends. I even use a level and stop when I reach 30 or 90. Any thoughts on what I can do to fix this?


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## telsa (May 22, 2015)

Practice.


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## ralpha494 (Oct 29, 2008)

Assuming that you are talking about an offset using 30 degree bends, and that you are off by an inch sounds like you are measuring the overall offset distance and not the bottom to bottom distance. That way it doesn't matter which size pipe you are using, the multiplier is still going to be two. It's all about the cosecant, man.


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## frenchelectrican (Mar 15, 2007)

Dizzykidd said:


> I don't know what I am doing wrong, but if I try to bend let's say a 30 degree bend it comes out about an inch bigger. The same thing happens with my 90 degree bends. I even use a level and stop when I reach 30 or 90. Any thoughts on what I can do to fix this?


All the 30 degree bends I know they have multipulier of 2 but any other bends you will need to get a chart to get the correct number of mesurement for correct bends.,,

However you will have to measure bottom to bottom on the offset bends.

For 90 degree bends .,, for most common 1/2 inch EMT benders most are useally at 5 inches radius but the larger one useally at 8 inches unless they are marked on the side of the shoe to tell you the distance to start bend at 0° spot.


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## MechanicalDVR (Dec 29, 2007)

Dizzykidd said:


> I don't know what I am doing wrong, but if I try to bend let's say a 30 degree bend it comes out about an inch bigger. The same thing happens with my 90 degree bends. I even use a level and stop when I reach 30 or 90. Any thoughts on what I can do to fix this?


Buy this:










and a few sticks of EMT and practice bending offsets.

You'll be fine.


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## Bird dog (Oct 27, 2015)

Use the same bender every time.
10 degree offset multiply depth by 6
22.5 x 4(?)
30 x 2
45 x 1.5
60 x 1.25


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## active1 (Dec 29, 2009)

Bird dog said:


> Use the same bender every time.
> 10 degree offset multiply depth by 6
> 22.5 x 4(?)
> 30 x 2
> ...


Bend multipliers are:

15 deg = 3.9
22 1/2 deg = 2.6
30 deg = 2
37 1/2 deg = 1.6
45 deg = 1.4
60 deg = 1.5

Your probably measuring it wrong


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## RePhase277 (Feb 5, 2008)

Make sure that you are measuring bottom-to-bottom and not bottom-to-top. The latter method will put you off by one conduit diameter too big.


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## drewsserviceco (Aug 1, 2014)

Dizzykidd said:


> I don't know what I am doing wrong, but if I try to bend let's say a 30 degree bend it comes out about an inch bigger. The same thing happens with my 90 degree bends. I even use a level and stop when I reach 30 or 90. Any thoughts on what I can do to fix this?



What are you using to locate your layout lines in the bender: front of shoe, the line or the notch?

The way I'm reading your question is, your bend is running an inch long. Example: you're looking for an 11" 90* and end up with a 12". 

More accurate descriptive words would go a long way. Is the stub of the 90* LONGER? Is the bend 1" more OPEN than desired? Is the offset 1" DEEPER or TALLER than desired?

We need a little more info before we can help.


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## Dizzykidd (Aug 3, 2016)

Yes if I try for a 11" 90 I get probably around 11.5. A journeyman did try to help and told me maybe I'm not putting enough foot pressure


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## Bird dog (Oct 27, 2015)

Dizzykidd said:


> Yes if I try for a 11" 90 I get probably around 11.5. A journeyman did try to help and told me maybe I'm not putting enough foot pressure


He might be right. You have to put all the weight on it you can like that conduit is going to grow legs and get off the floor on you.


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## bill39 (Sep 4, 2009)

RePhase277 said:


> Make sure that you are measuring bottom-to-bottom and not bottom-to-top. The latter method will put you off by one conduit diameter too big.


I gotta agree with the above reply. On offsets make sure you are measuring from botttom-to-bottom and on 90's the measurement should be to the back of the bend. At least that's how many do it.

NOTE: for offsets bottom-to-bottom and center-to-center should be the same measurement.


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## bill39 (Sep 4, 2009)

If you're using an EMT hand bender and think foot pressure may be a problem, put pipe on the floor with the long end against a wall or some other stationary point. This will help.

Other than that, you may need to eat more Wheaties.


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## drewsserviceco (Aug 1, 2014)

Dizzykidd said:


> Yes if I try for a 11" 90 I get probably around 11.5. A journeyman did try to help and told me maybe I'm not putting enough foot pressure



Foot pressure is a good place to start, it may be that you're still a little green and the pipe in the bender is sliding off your mark a little. Things like this improve with practice. 

If you are off by a consistent number each time, that seems to me like an error in layout versus a mechanical movement/technique issue. 

Example: consistently off by 1 1/8" and your bending 3/4" emt, I would think you're measuring from the wrong side of the conduit (3/4" emt being 1 1/8" OD). 

Another famous mistake we all make on occasion is measuring to the wrong side of our level when taking the measurements for the bend, then having the pipe be off by the thickness of our level. 

Your best bet is to adopt a system that works for you (you can take one from a Jman you work with or combine several Jman's to make your own) where you can produce with consistent accuracy, and then don't deviate from that system. Just a list of steps to help you stay focused on what you're trying to accomplish with the conduit, how you're going to get there and what the bends need to do. (Things like taking measurements working from one direction only, or adopting a practice that all my measurements are Center-Center or Bottom-Bottom). 

It becomes your checklist as you're doing a bend. It won't be long before it becomes a reflex and it just happens and you're not thinking about it. It's developing these reflex sort of "rules" that takes the tedious thinking out of what you're doing and it allows you to focus on the task at hand and work efficiently.


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## PlugsAndLights (Jan 19, 2016)

active1 said:


> Bend multipliers are:
> 
> 15 deg = 3.9
> 22 1/2 deg = 2.6
> ...


Looks like there's a mistake/typo in the numbers. Multipliers are 
decreasing with increasing angles up to 45deg but 60 deg goes 
the wrong direction. Think maybe 60 deg should be 1.*1*5.
P&L


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## Dizzykidd (Aug 3, 2016)

Thanks for all the advice guys. I will definitely work on the foot pressure and double check that my measurements are bottom to bottom.


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## active1 (Dec 29, 2009)

PlugsAndLights said:


> Looks like there's a mistake/typo in the numbers. Multipliers are
> decreasing with increasing angles up to 45deg but 60 deg goes
> the wrong direction. Think maybe 60 deg should be 1.*1*5.
> P&L


Your right. Was rushing. 
60 degrees I use 1.2.
10 degrees would be 6.
Hard to remember when Vegas is a city of cable.


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## bill39 (Sep 4, 2009)

active1 said:


> Your right. Was rushing.
> 60 degrees I use 1.2.
> 10 degrees would be 6.
> Hard to remember when Vegas is a city of cable.


With calculators everywhere these days there is no reason to not use the more precise values for these angles. It makes a difference especially when the larger the offset distance:

15 deg use 3.864
22.5 deg use 2.554
45 deg use 1.414
60 deg use 1.155

Also, remember to deduct the gain, especially on larger radius conduit. Every little bit can make a big difference and then the frustration sets in.


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## kg7879 (Feb 3, 2014)

Dizzykidd said:


> I don't know what I am doing wrong, but if I try to bend let's say a 30 degree bend it comes out about an inch bigger. The same thing happens with my 90 degree bends. I even use a level and stop when I reach 30 or 90. Any thoughts on what I can do to fix this?


If you are using the 30 degree bubble on a level you have to keep a couple things in mind. If the floor isn't level then you will be off and second sometimes those levels are not the accurate.


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