Is deduct only for ninties?
- Thread starter zappy
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jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
The pipe will lengthen, so deduct would count. You will end up cutting a short piece off.
http://www.porcupinepress.com/_bending/ConduitBending.htm
Great conduit bending website. Use the gray rectangle on the left hand side of site page to see all the different pipe bends (ninetys, offsets, three and four bend saddles, kicks, etc..). Hope this helps!
Great conduit bending website. Use the gray rectangle on the left hand side of site page to see all the different pipe bends (ninetys, offsets, three and four bend saddles, kicks, etc..). Hope this helps!
cadpoint
Senior Member
- Location
- Durham, NC
What I think your asking is there a way to determine where to start your bends, no.* A multiplier of 60^ is 1.2 and is your smallest multiplier when bending, and in fact is not a deduction.
*Well you can approximate once you determine your multiplier, but it sounds like your going to have to cut off the existing run, IE your to close...
Your multiplier for 30^ is 2: thus 2x 17" = 34". This will get you past object with no distance between what your trying to get by, your flush and touching object your trying to get past.
Your bending an offset! The distance your traveling is measured by determining the depth that the conduit needs to pass by your 17", then you use a multiplier of the desired angle you want to bend.
I'd add the distance of a mineral-lac (stand-off)+ .1/2" if you need to, or add the depth of insulation if required.
Mark the sum on two place on conduit and bend on the arrow to the multiplier, do not reverse the shoe, just turn it over...
You need to buy an Ugly Book
So say a 90 degree bend the shoe say's 5" deduct. So would a 45 degree be a 2.5" deduct?
Zappy, if you measure from the end of your conduit to the wall and the measurement is 65", you need a 65" (90 degree bend) to go up the wall. take a full length of pipe and place it on the floor, measure 65" and place a mark on the pipe, THAN take the 5" deduct that is stamped on the bender and subtract that from the 65" you marked on the conduit on the floor. Now you should have a mark on the pipe at 60". Now take your bender and face the end of the pipe you started measuring from and place the arrow (stamped on the bender) on the 60" mark and bend until it is a 90 degree bend. The deduct 5" is for 90 degree bends only for that specific bender and conduit size
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No I am putting one bend in a nipple.
No I am putting one bend in a nipple.
I not talking about a offset. Just a kick. And I'm wondering how you can cut and thread a piece of pipe first then put a kick in it and make it fit. There must be some gain that needs to be subtracted. So say 1/2 rigid 90degree bend you would gain 3"1/4. So what would you gain on a 30degree bend? A third of 3"1/4???
No I am putting one bend in a nipple.
What I think your asking is there a way to determine where to start your bends, no.* A multiplier of 60^ is 1.2 and is your smallest multiplier when bending, and in fact is not a deduction.
*Well you can approximate once you determine your multiplier, but it sounds like your going to have to cut off the existing run, IE your to close...
Your multiplier for 30^ is 2: thus 2x 17" = 34". This will get you past object with no distance between what your trying to get by, your flush and touching object your trying to get past.
Your bending an offset! The distance your traveling is measured by determining the depth that the conduit needs to pass by your 17", then you use a multiplier of the desired angle you want to bend.
I'd add the distance of a mineral-lac (stand-off)+ .1/2" if you need to, or add the depth of insulation if required.
Mark the sum on two place on conduit and bend on the arrow to the multiplier, do not reverse the shoe, just turn it over...
You need to buy an Ugly Book
I not talking about a offset. Just a kick. And I'm wondering how you can cut and thread a piece of pipe first then put a kick in it and make it fit. There must be some gain that needs to be subtracted. So say 1/2 rigid 90degree bend you would gain 3"1/4. So what would you gain on a 30degree bend? A third of 3"1/4???
I meant to say gain. Sorry.
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jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Zappy, I want to say yes - if a 90 bend is 5" then a 45 should be 2.5", but I am leery. The math seems right, but benders vary and I do not want to commit to it. I have my benders handy but no conduit to test.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Zappy, quit saying you are sorry. We all mis-post a reply here and there.
You are polite enough (this a compliment)-you need not apologize.
It is always cool to see you here. Where in CA are you?
You are polite enough (this a compliment)-you need not apologize.
It is always cool to see you here. Where in CA are you?
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
There is no deduct for a kick. You have to think about shrink, but it is a different concept. The notch on your bender is the center of a kick.
Generally, you can ignore thinking about shrink, because you have the option to stop running the portion of the conduit you're working on, begin at the other end to meet yourself in the middle and avoid the math.
Look for the shrink values on your bender. 30 degree kicks are 3/16" of shrink for every inch of offset. A kick is technically an offset too.
Generally, you can ignore thinking about shrink, because you have the option to stop running the portion of the conduit you're working on, begin at the other end to meet yourself in the middle and avoid the math.
Look for the shrink values on your bender. 30 degree kicks are 3/16" of shrink for every inch of offset. A kick is technically an offset too.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
It would be 17 x 2 (30 degree multiplier) so you should mark 34" from whatever you're trying to hit (even with just a kick)
Thank you George. You lost me on the second paragraph. Don't you mean 1/4" of shrink for a 30 degree bend? I thought because your bending at a radius, there would be a gain, but your saying it's shrink. I going to experiment this weekend. Thanks George.
Why thank you. That is nice to hear. I'm in Northern Ca. Bay area, there abouts. Take care.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
I don't see how you gain pipe by bending it, that doesn't make sense. Think about a 10' stick of pipe. Bend it a little, it will lot be as long, measured along the same axis.
Imagine you want the kick to be in the horizontal plane before a 90. If you work your way to the 90 it is more difficult to get the 90 to contact the wall, because the pipe shrinks. If you work the other way, 90 first, then kick, it is more manageable, because you don't care about shrink after your bends.
For every bend, you gain a little bit of distance. We typically measure straight-line run distance. Every bend shortcuts that distance with a curve.
For example, put a 90? bend on a 10' stick and of course it is no longer 10' long in one direction... but add the distance covered in both directions and it will be greater than 10'. The amount greater than the straight length is your [90?] gain.
On paper, conduit per degree of bend is constant. Varies a little in actual bending.
Gain can be determined by formula, but it is not linear... i.e. the gain of a 45? bend is not 1/2 that of a 90? bend. Let's see... the 45? arc length is (pi)r/4 while a 90? arc is (pi)r/2, but the straight-line distance of a 45 is 2r?tan22.5?, or approximately 0.828r, while that of a 90 is 2r. So the gain, on paper, is 45? @ 0.828r ? (pi)r/4 and 90? @ 2r - (pi)r/2. If you trust my math, they reduce to 45 @ 0.0426r and 90 @ 0.4292r.
kwired
Electron manager
- Location
- NE Nebraska
I think Zappy is asking how to accurately measure and mark a 45 degree "stub" (half of a 90 degree stub).
He used the word "kick" which many interpret as meaning "offset".
I have needed to do this a few times before, but know of no sure way to get it right the first time. And many of those times it is not necessarily 45 degrees but just random angle that we need to match. With EMT you usually end up making it long and cutting it. With rigid or IMC that may make it difficult to thread if you have to cut after bending so I see his problem.
He used the word "kick" which many interpret as meaning "offset".
I have needed to do this a few times before, but know of no sure way to get it right the first time. And many of those times it is not necessarily 45 degrees but just random angle that we need to match. With EMT you usually end up making it long and cutting it. With rigid or IMC that may make it difficult to thread if you have to cut after bending so I see his problem.
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