Step 10: Bending

WARNING: Before you decide to bend PVC pipe, please consult the ‘Cautions’ section of this Instructable. Bending PVC pipe involves heating the pipe close to its melting point, which can cause the PVC to out-gas chlorine and dioxins. These chemicals can cause harm to the human body over long periods of exposure. Perform the heating of PVC outdoors or in a well ventilated area such as a garage with the door(s) open. If you have to do it in a basement or other interior room, use a respirator or a fan with an open window.

To bend PVC pipe you will need a few supplies. The first is a PVC Bending Jig, whichI have uploaded plans for, located here for SketchUp. This jig will allow you to bend PVC controllably and easily. The trick of bending PVC is that your bend may not end up exactly where you want it in the overall position of the pipe length, so it is suggested that you bend the pipe FIRST, and then cut it to length.

To bend PVC pipe you need:

-  PVC Bending Jig (free plans available here)
-  PVC pipe
-  Heat Gun or Propane Torch
-  Sand or Cat Litter
 PVC End Caps or Duct Tape

1.  Place duct tape over one end of the PVC pipe segment to be bent. This will allow you to fill the PVC pipe with filler.

2.  Pour sand or cat litter into the opposite end, filling the entire PVC pipe to be bent with the filler.  Shake to distribute and top off if necessary.  You’ll need to fill the entire pipe.

3.  Place an additional duct tape over the remaining opened end of the PVC pipe segment.

4.  Heat up the PVC pipe with a heat gun or propane torch along the area to be bent.  Apply heat until the area appears pliable. Don’t overdo it, or you will deform the PVC.

5.  Once the desired softness of the PVC pipe is achieved, place the softened area into the joint position on the PVC bending jig.

Using the force of your hand, move the top part of the jig to the desired angle and hold in this position for about a minute or until you think it has cooled.  You can use the holes in the jig to hold the peice in place.  Make sure it is completely cool before removing from the jig.

7.  Perform the cuts on each end of the newly curved pipe as needed.

<p>You meentioned about cutting the pipe shorter for the correct length. Is this for the outside length or inside? I want to start a project that the inside should be 48&quot; wide. Should the pipe be say 2&quot; longer because both ends will be in an elbow or a tee, to hold the inside measurement of 48&quot;? Your article was very helpful. Thank-You. </p>
<p>id love to make pvc stuff put in here Finland we don't have the glue bondable pvc pipes. we have pp pipes and male female muff pvc pipes. So it is hard to do stuff that has end caps on both ends of the pipe.</p>
pvc cutting jig<br>
I need to make a PVC right triangle. Anyone got any ideas how? I can't find and acute PVC angle.
<p>You could use a combination of obtuse angles to create an angle greater than 180 degrees. It wouldn't look very good, but it could work.</p>
<p>Just a thought. Buy a T-fitting and cut out the middle. Heat gun and bend it closed w a drop of PVC glue?</p>
Getting ready to make curtain rods out of pvc do not want rings to peel paint, will the fusion paint withstand the use?
Very useful! Thanks!
<p>Hi,</p><p>Struggling on how to make a pvc type screw such as the image in the website address below. <br>Would appreciate any hints or tips.. Thanks in advance :) <br>http://gardening.onlineshoppingoutlets.info/wp-content/uploads/2015/05/41yzfn8hXrL-184x184.jpg</p>
<p>I always had trouble &quot;dry-fitting&quot; as too often the pieces would simply not come apart.<br>I finally solved this by using my 1/2&quot; fine-tooth bandsaw blade to cut 1/2&quot; into the ends. That 1/2&quot; and band-saw-thin cut is just enough to relieve pressure for knock-down and refitting. For non-plumbing jobs, I still have the option of using PVC glue or screws for a final assembly, but test-fits are a dream.</p>
it says on the can &quot;no sanding required&quot;
<p>I always sand before I glue or paint, just comes out better.</p>
I know, but the manufacturers sometimes have embossments on the pipes and fittings and if there is anything more filthy, it is PVC from Home Depot.<br><br>Plus I come from the old school of 'sand, paint and sand again'. Its just a recommendation...
&nbsp;you can just get pvc primer and then paint over that
<p>Primer is sort of expensive, I would rather buy a sheet of 220 grit and sand.</p>
<p>I am trying to make a VC canopy/awning that can be taken down when not in use. So I don't want to cement it together. Perhaps I am not strong enough, but I am unable to push the fittings together. Is there some sort of lubricant that would help with this effort?</p>
<p>This is one of the best instructables, everything i ever wanted to know about pvc and hell i learned stuff i didnt know. Thank you. </p>
For Band Saws, I have found that the ones I have access to work rather well. For one, they were both designed to cut steel rather quickly, and two, they both have adjustable drop rates. (Both are horizontal band saws)<br /> <br /> And for Pipe cutters, they will work, you just have to be careful with them. I've used them in the past to get really square and even cuts when I&nbsp;didn't have access to a band, chop, or miter saw. Although you do have to really crank the blade in after getting a nice initial groove started.<br />
<p>agreed, i have been using a twirly pipe cutter, seems to do the trick, as mentioned first pass has to be straight, and bam...hands get a little soar after cutting a bunch but it works</p>
yes thank you for saying that XGundam05 i have found that my metal pipe cutter works almost as well as anything else I have used including a dremel with a metal bit in it.<br />
Using a wood saw is just silly? ive tried using both hacksaws and wood saws and the wood saws work great, they cut so much faster and give you a straighter cut.
<p>agreed, i have used a woodsaw and a jig to get awesome straight fast cuts with pvc and ABS...</p>
<p>Will ABS Sch 40 support the weight of an average person (in a rectangular frame with a sex sling attached to steel eyebolts)?</p>
<p>I am just getting started in PVC and mostly want to use it for dart guns/ nerf mods. some of the things I have read on this subject uses CPVC what is that? </p>
Great inst. You didn't mention that PVC is available in heavy &amp; strong, but expensive &quot;Schedule 40&quot; and also available in light weight but cheap 200 psi pipe. I buy both for different projects. <br>Look at my posting of &quot;Spiral Cable Wrap&quot; made from PEX pipe.
<p>I want to paint decorations on a PVC pipe. I can spray it first with the Krylon Fusion Paint, but then what type of paint should I use for the decorative painting? What sort of &quot;sealer&quot; should I use over the paint to keep the paint from chipping off as it will be outside?</p>
Great instructable. I use my miter saw to make cuts but I turn the blade backwards so the teeth are opposite of that for wood cutting. Really smooth cuts this way.
<p>You can also form PVC using boiling water. I find it is easier to control the heat. </p>
<p>You can cut PVC safely on a table saw, I have done it quite a bit in the past. A compound miter saw is a better choice, but most compound miter saws can only handle stock up to 4 inches. For larger PVC, you need to build something akin to a modified crosscut sled. Mine wasn't two pieces, but he pictures will give you an idea of what you need. </p><p>Thanks for the 101! Here are two Instructables on locking joints people may be interested in, feel free to add to 101!</p><p><a href="http://www.instructables.com/id/Quick-And-Easy-PVC-Lock-Joints/" rel="nofollow">http://www.instructables.com/id/Quick-And-Easy-PVC...</a></p><p></p><p><a href="http://www.instructables.com/id/PVC-Bungee-Joints/" rel="nofollow">http://www.instructables.com/id/PVC-Bungee-Joints/</a></p>
Can you clean old PVC pipes and joints to reuse
Excellent !
An idea to prevent PVC from bending too much in long lengths: run thin gauge steel wire (about $7 for 100 feet from hardware stores) through holes on each end of the PVC tubing. Let the tension be in the steel instead of the plastic. If the piece is subject to possible bending in any direction then the wire will have to run along 4 sides, 90 degrees apart around the tube. You can drill four holes in each end and run 1 long wire through them all.
Also, only the glue method should be used for pressurized applications, like making pumps or launchers. <br> <br>I like the screw idea for non-pressure :)
Has anyone ever used rivets instead of screws to attach PVC?
An extra step for your instructable.<br /> <br /> I remember discussing this somewhere else on instructables but can't really remember so I'm just gonna give you the link to the site that promotes it.<br /> <br /> <a href="http://www.thepipeviper.com/" rel="nofollow">www.thepipeviper.com/</a><br /> <br /> It's a site that sells a tool with which you can cold bend a pvc pipe.<br /> <br /> I live in Belgium (Europe) and followed industrial science in highschool. We had electricity there which involved alot of pvc bending. I however never heard off hot bending pvc before I came to this site.<br /> <br /> We always bended our pvc cold using the same tool that that company sells. It doesn't damage the pipe and keeps the hole inside open as much as it would if you didn't bend it. It's really handy, easy and there is no danger at all of hurting yourself. And it doesn't take more then a 15 year old boys strength to do it :)<br /> <br /> So check it out I'm sure you'll find it interesting :)<br /> <br /> Michel<br />
I looked at the site you linked. Very interesting tool. They don't have a FAQ page, so I thought I'd ask you, since you have experience:<br><br>Is this suitable only for conduit applications, or can it be used for household water systems? I'd think that even though the pipe is 'not damaged' by cold bending, it may be weakened enough that it would not reliably carry pressurized water for household cold and hot water. So, is this used for water, or only for conduit?
I remember the plumbing classes in my highschool using the same cold bending method I described above for your usual kitched plumbing. You are right that the structure is weakend but the same goes for hot bending (in both cases you are stretching out the material over a longer length)<br><br>So yes you can use it to run hot and cold water unless you plan to do some crazy bending with it (over 270 degrees) but for normal 90 degree bends it should do fine :)<br><br>
Wow. Thanks for the quick reply and information. I may stick with solvent-welding to molded fittings for plumbing, but I have some ideas for running conduit for which this might be just the ticket.<br><br>I will have to see if a regular length of flexible spring will work almost as well.
I am always confused about the quantity of cement to apply. <br><br>Should it be:<br>1. A thin layer, or<br>2. Very generous?<br><br>Can I use Acetone as PVC pipe cleaner as well?<br><br>Thanks.
I would recommend a thin layer. Once the cement hits the plastic it begins to melt, so you really don't need too much.<br><br>And yes, you can use acetone as pipe cleaner as well, but I recently found out that those sandpaper foam pads you get in the hardware store work just as good to prep the connection points, as well as remove the ink and marking.
you can also paint plastic with Killz or Benz paints, they're alot cheaper but you have to brush it on, and home depot will tint your Killz for you.
In Australia there are 2 types of PVC. Non-Pressure or Down Pipe Grade, or Pressure Grade which is used to transport liquids.<br>The larger pipes 90 mm, 100mm up to 230mm &amp; beyond. are great for buildings. Pot plants, Hydroponics even a wind tunnel with the 230mm.<br>The PVC off cuts can be picked up for free in the &quot;Poor Mans Bunnings&quot; or the rubbish point on a building site, along with timber scraps, bits of copper pipe, insulation, etc . For the larger pipes go to a New Estate site &amp; ask if you can have the left over water &amp; drainage off cuts (230mm). They'll give them to you, mostly. It saves you having to get rid of them. I ended up with enough house bricks to build a house once. They said, &quot; you pick them all up you can have them.&quot; All different colours, but, Hey! If you don't ask you don't get.
This is an instructable that doesn't teach you how to build a dang thing! This is also one of the most helpful instructables I have ever seen, complete and straightforward!<br><br>Great job.
Great instructable! I especially liked that you design in Sketchup. I down loaded the fittings you showed and have been trying to design something from them. I seem to have a problem with lining up the pvc pipe and the fittings. No matter how hard I try I can't seem to get them straight. I am obviously doing it all wrong, and I do mean ALL WRONG! The sketchup tutorials were no help. Neither was Google Warehouse. Any suggestions on how to start getting things straignt? (An Instructable perhaps)<br /> <br /> Any suggestions would be appreciated.<br /> <br /> Thanks
I am building a boat out of 1.5 inch PVC and had the same problem with making the 90 degree angles exactly 90 degrees. Build a gig out of 2x4 or 2x6 and not only will your joints be parrell but you can also make a press into it so the pipe will seat completly into the fittings. Also you can make a simple gig (two demental) using a sheeet of plywood and pieces of square 2x4 blocks. I can send you a picture and dementions if you like. (Fallslakebob@gmail.com). Bob
Thanks for the reply bobjacksonjr.<br>Some people think that building a jig to get something you're building built right is a waste of time and trouble but it really isn't especially if you really need to get it right. So you are right <br><br>To get real pipe to make real 90 degree angles is not a problem for me. What I was talking about was how to get real 90s in Sketch up. The 3 dimensional manipulation that you have to do can be a little tricky. I have gotten somewhat better at it since I wrote the post last year but there is still a lot of hear pulling to get it right. Maybe it is a good thing I keep my hear short::) If I am building something with PVC I will use the fittings in the design process to get the angles I need. Getting it to look right in Google Sketchup is the challenge.<br><br>Wish you success in your boat;<br><br>Joen
I hear filling the PVC pipe with hot sand also is a method for bending the pipe.
On my last project I considered buying a PVC cutter, but after looking at one in the store I borrowed my wifes ratcheting action pruning shears instead. Sharpened the blade a bit and It worked like a champ!

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