How to Bend Pipe Without a Pipe Bender
Intro: How to Bend Pipe Without a Pipe Bender
Ahoy! So you have some pipe that needs to be bent but you don't have a pipe bender. Well no problem! This instructable will show you how to do it using sand and some creativity.
The pipe shown here is 4130 steel - 3/4" in diameter with a wall thickness of 0.035".
The point of using sand is to support the pipe (keep it round) so that it does not buckle when bent. It worked for me!
Plan ahead - the end closest to the bend will likely have to be cut off and discarded.
The pipe shown here is 4130 steel - 3/4" in diameter with a wall thickness of 0.035".
The point of using sand is to support the pipe (keep it round) so that it does not buckle when bent. It worked for me!
Plan ahead - the end closest to the bend will likely have to be cut off and discarded.
STEP 1: Pack Your Pipe
The first thing to do is to plug one end of the pipe. I used a small carriage bolt that fit snugly in the end. The next step is to fill the pipe with sand. I used beach sand. The sand should be nice and compact to stop the pipe from buckling. I used a rod to tamp the sand but what really packed it in was tapping (bouncing) the pipe on a concrete paving stone.
STEP 2: Bend!
Clamp one end to a form. Here I used a wine barrel planter and then added a rounded block (that just happened to be in my workshop) to get a tighter radius. You will likely need a lot of leverage to bend the pipe. This piece was 4 feet long and it took some muscle to get the bend.
STEP 3: Finish It Up
Cut the deformed end off. Clean out the sand. I used a piece of string with a rag on the end to get all the sand out.
The picture below shows the slight dimple in the center of the bend. Unfortunately the method is not perfect but I am very happy with how this turned out (the pipe is a new steerer arm for my bamboo box bike https://www.instructables.com/id/Intro-How-to-Design-and-Build-a-Bamboo-Cargo-Bik/ )
One last thing - you can heat up the pipe with a torch before bending to soften the metal and get a cleaner bend. I did not want to mess with the temper of the pipe so I did not do this.
The picture below shows the slight dimple in the center of the bend. Unfortunately the method is not perfect but I am very happy with how this turned out (the pipe is a new steerer arm for my bamboo box bike https://www.instructables.com/id/Intro-How-to-Design-and-Build-a-Bamboo-Cargo-Bik/ )
One last thing - you can heat up the pipe with a torch before bending to soften the metal and get a cleaner bend. I did not want to mess with the temper of the pipe so I did not do this.
44 Comments
Lesrev 5 years ago
justin367 8 years ago
Can you use this technique on a 2 inch pipe.
strayturk 10 years ago
My inner perfectionist wants to provide one correction, with your permission. The material you used (the 4130 steel) is most probably considered a tubing, rather than pipe. The difference is in their measurements and intended use. You measure a pipe by its internal diameter and you don't worry about wall thickness, whereas a tubing is measured by its outer diameter and wall thickness.
For all practical purposes, the bending method you described would apply to both.
Have a perfect day! :)
kwhit190211 10 years ago
bowen5400 8 years ago
ayasbek 10 years ago
antioch 10 years ago
Thanks for your addition, too.
altomic 10 years ago
I watched a doco on making slide trombones. to make teh bend they filled the pipe(brass) with briney/salty water. sealed each end with corks and then placed it in a larger freezer. once the briney water had gone almmost hard (it won't completely freeze or they didn't allow it to freeze) and that's when they bent it and it didn't crinkle.
kwhit190211 8 years ago
They used this method in bending because that tubing is very thin and if you filled it with sand instead. You might end up with a wrinkle bend, that's definately not good for the instrument.
clubagreenie 10 years ago
If doing multiple bends you need to resettle the sand between bending or you will kink it. Voice of experience. If you look at the elaborate designs in F1 exhausts etc from the 70's and 80's (pre titanium days) hey were all done by hand from one piece of tube.
pictsidhe. 8 years ago
Wrong, much like the article. If you heat, you need to let the gas out. If you let the sand out, the pipe will kink. I weld one end shut, weld a large nut on the other, then bang, rattle the sand down before finally screwing a large screw as tight as i can into that nut. The pipe has to be packed very hard to prevent kinks.
kwhit190211 10 years ago
ecurtain 10 years ago
Eh Lie Us! 10 years ago
spiderham 10 years ago
kwhit190211 10 years ago
randomray 10 years ago
Thanks for sharing .
kwhit190211 10 years ago
When bending pipe you want to make sure that the pipe is level or you can end up with a twist in it. And, they are hard to get out.
randomray 10 years ago
kwhit190211 10 years ago
And, as someone here has stated they use salt. Well, I've lost tract of how many feet of pipe that I have burned out that was clogged with salt over the years. We always ran into it with air lines bent around the bustle pipe of a blast furnance.