kicks in pipe

[spy44der]

is there a formula that you are suppose to use when you have to make a 90 degree and have to add a kick to the pipe,are you suppose to add length to the pipe to make up for the kick you put in??

 

[George Stolz]

For a 30? kick, you add a quarter inch per inch to cover the kick.

So you have a 90? finishing at 60" and need a 8" kick at the end, you bend the 90? at 62", back up 16" and make a 30? kick.

 

[brother]

For a 30? kick, you add a quarter inch per inch to cover the kick.

So you have a 90? finishing at 60" and need a 8" kick at the end, you bend the 90? at 62", back up 16" and make a 30? kick.

george the conduit bender teacher. just remember that you can use the cosecant of what ever angle to multiply for the height of what you want to bend at and it will tell you how far back to bend the pipe for the kick.

 

[Smart $]

george the conduit bender teacher. just remember that you can use the cosecant of what ever angle to multiply for the height of what you want to bend at and it will tell you how far back to bend the pipe for the kick.

For those that don't know, the cosecant is the inverse value (as in 1/x) of the sine.

Example:

csc 30? = 2.000
sin 30? = 0.500
1 ? 0.500 = 2.000​

Just mentioning this in case one has access to trig table without the inverse functions (i.e. only sine, cosine, and tangent).

 

[Pierre C Belarge]

All that sounds so complicated, much more complicated than "by eye". :grin:

 

[daleuger]

All that sounds so complicated, much more complicated than "by eye". :grin:

Or "looks good from my house...."

 

[Fulthrotl]

All that sounds so complicated, much more complicated than "by eye". :grin:

unless it's 4" grc, that you have to cut and thread before you bend.......

"just add a little bit" takes a fair amount of experience to define what
"a little bit" is.....

 

[spy44der]

For a 30? kick, you add a quarter inch per inch to cover the kick.

So you have a 90? finishing at 60" and need a 8" kick at the end, you bend the 90? at 62", back up 16" and make a 30? kick.

ok,let's say I want a 25''x60'' bend and I need a 3'' kick,to go over a beam and into a J-box?

 

[hardworkingstiff]

All that sounds so complicated, much more complicated than "by eye". :grin:

I'm with you Pierre. I was pretty good in Geometry, back in 1969. I've learned to "feel" and "see" what needs to be done.

 

[Smart $]

ok,let's say I want a 25''x60'' bend and I need a 3'' kick,to go over a beam and into a J-box?

Are you asking how to bend this, or how to meaure and cut the conduit first so the dimensions are good after it is bent?

Measure and cut prior to bending is best left for "shapes" which require threading before bending, when tooling will not permit threading, or presents a major difficulty afterwards. The shape you have given can be cut and thread after bending in practically all cases (provided you have the proper tools for the job at hand).

To bend up your given example, make one leg true to the 90? bend... the one that don't have a kick in it. Bend the kick in the other leg. Measure and cut the kicked leg to exact required length.

 

[mayanees]

respect for the trade...

respect for the trade...

This thread represents a disappearing art in the industry, that of the experienced pipe bender.
As a 50 year-old engineer, I can recall some of the prettiest increasing/decreasing radius rigid aluminum/steel pipe bends in my early years at Scott Paper. They were works of art.
But as time went on, low-bidders got the jobs, and the craftsmanship suffered. And as budgets tightened, materials turned from rigid to thinwall or EMT.
But I have all the respect in the world for you guys who can run pretty pipe.

Same thing goes for exhaust systems. I recently hunted out an oldtimer to run dual 2" alumanized pipes out of a 6 cylinder split header manifold. Maryland Muffler did not disappoint.

John M

 

[izak]

George, when you say to make an 8 inch kick on 30 degrees, come back sixteen inches and bend,

to what mark on the bender do we need to match the mark at 16 inches?

 

[Rockyd]

If your using a hand bender like an Ideal, look at the bender. Where it says "BACK OF 90" make the "O" in OF your center of bend, it'll be pretty close. If your a decent bender, it should get you within an 1/8" after a couple of times. If not, your stuck with running pipe behind the walls, and ceiling tiles !

 

[Smart $]

George, when you say to make an 8 inch kick on 30 degrees, come back sixteen inches and bend,

to what mark on the bender do we need to match the mark at 16 inches?

There is no mark for middle of a 30? bend on most benders. You can approximate and be pretty close... it would be 2/3 the way between your 0? indicator (arrow, notch, etc.) and the 45? bend center indicator (usually a notch).

 

[izak]

yeah,

its usually about 1/4 inch ahead of the notch for 30 degree bends on traditional "benefield" benders...


i used to 'calibrate' every one i used until i figured out that on that style, the center of the 30 is about 1/4 inch closer than for 45


and yes, i DO scribe marks on benders to show the center of 30 degree bends, because when i am making kicks to exact measurements, it is often ALOT easier to measure back say 16 inches from the back of the 90 (for 8 inch kick) and place the 16 inch mark on my pre-determined 30 degree center, bend to 30 degrees according to my level,


and not measure the kick


because i know that it will be within 1/8 inch of what i want


THAT is precision pipe bending

 

[nunu161]

10 degrees- 1/16 shrink
22.5 degrees-3/16 shrink
30 degrees- 1/4 shrink
45 degrees- 3/8 shrink
60 degrees- 1/2 shrink

 

[George Stolz]

THAT is precision pipe bending

THAT is more precise than I've ever tried to be.

 

[Rockyd]

I'm taking my bender and going home!