PVC pipe is a great material for making things. If you ever need to bend the pipe, here's how to do it.
The trick is to fill it with sand before heating the plastic and bending it. Normally, the pipe would pinch closed in areas where it is bent, but the sand prevents that. When the heat forming is finished, you just drain out the sand.
The trick is to fill it with sand before heating the plastic and bending it. Normally, the pipe would pinch closed in areas where it is bent, but the sand prevents that. When the heat forming is finished, you just drain out the sand.
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Signing UpStep 1: Safety while heating PVC
We love plastics for what they do for us, but plastic manufacture and decay tend to pollute the environment and negatively affect our health.
Vinyl Chloride, one of the components of PVC, is carcinogenic. When it is locked up in the polymer, however, it is much safer to be around. In my years of experience working with PVC, I have not noticed any adverse effects on my health from being around it.
Always work in areas with good ventilation. If you do get caught in a cloud of smoke, hold your breath and move to clean air.
When heating PVC with a gas stove or propane torch, try not to let it burn. Smoke from burning PVC is bad. With experience one burns it less and less. Don't panic the first time you do burn some. It scorches, but doesn't immediately burst into flame. Move the material away from the flame and try again. Don't breathe the smoke. Smoke avoidance comes naturally for most people.
While heating PVC over a gas flame, keep the plastic an appropriate distance from the flame to avoid scorching the surface before the inside can warm up. It takes time for heat to travel to the center of the material being heated.
Keep the plastic moving, and keep an eye on the state of the plastic. When heated, the PVC material is flexible, like leather. Beyond this stage, you risk scorching it.
A word from James, the plastic engineer -- "Just a word of warning, PVC can handle some high heats but if it catches fire, you wont be able to put it out, it does not need oxygen to burn so don't do this inside".
I do work inside, but my house is made of cement and has good ventilation. MAKE SURE THAT YOU HAVE GOOD VENTILATION. PLAY WITH FIRE -- CAREFULLY.
Vinyl Chloride, one of the components of PVC, is carcinogenic. When it is locked up in the polymer, however, it is much safer to be around. In my years of experience working with PVC, I have not noticed any adverse effects on my health from being around it.
Always work in areas with good ventilation. If you do get caught in a cloud of smoke, hold your breath and move to clean air.
When heating PVC with a gas stove or propane torch, try not to let it burn. Smoke from burning PVC is bad. With experience one burns it less and less. Don't panic the first time you do burn some. It scorches, but doesn't immediately burst into flame. Move the material away from the flame and try again. Don't breathe the smoke. Smoke avoidance comes naturally for most people.
While heating PVC over a gas flame, keep the plastic an appropriate distance from the flame to avoid scorching the surface before the inside can warm up. It takes time for heat to travel to the center of the material being heated.
Keep the plastic moving, and keep an eye on the state of the plastic. When heated, the PVC material is flexible, like leather. Beyond this stage, you risk scorching it.
A word from James, the plastic engineer -- "Just a word of warning, PVC can handle some high heats but if it catches fire, you wont be able to put it out, it does not need oxygen to burn so don't do this inside".
I do work inside, but my house is made of cement and has good ventilation. MAKE SURE THAT YOU HAVE GOOD VENTILATION. PLAY WITH FIRE -- CAREFULLY.
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I agree that there are no known health benefits to breathing burning plastic. The art, not a difficult one to learn, is to not burn the plastic when you soften it. Yes, good ventilation is always important.
If forced to burn PVC will not produce chlorine but will emit dense acrid fumes containing noxious and toxic compounds including carbon monoxide, hydrogen chloride and possibly dioxins.
However PVC will not burn on its own, it needs continuous applied heat to char it.
Also, do you think this method would work with copper piping? I need to bend some into a radiator shape but I can't figure out how.
If you had a spring the right size then you could use it with heat for bending PVC pipe.
You can play with fire and not get burned. You just have to be careful. Keep work moving to avoid hot spots, and at an appropriate distance from the flame.
If you want to bend pipe into an exactly repeatable curve, you need something round to bend it around. Ideal would be a shape like a pulley wheel with a channel for the pipe to be pulled into as you wrap it around. That would help reduce flattening on the inside, keeping the pipe cross-section rounder.
You might be able to make such a round pulley wheel shape out of wood, if you have a router to gouge out the channel in the wood. That gets pretty high-tec with the need for tools, though.
The Pipe Viper looks great for bends 30" apart giving leverage to put a bend in PVC. I wonder about bending tight offsets though. A 3" inch offset requires 30 degree bends 6" a part. Add other tight bends in a 10' conduit & you'd have to be superman. It looks like a great tool & I don't understand why the Electrical suppliers haven't pushed it.
Zappenfusen
As far as I can tell, it is just as strong after bending as before. Chemically, I don't think you break any of the polymer chains by softening the plastic, or bending it.
Yes, it seems to be just as springy.
It doesn't become brittle.
Interestingly, it does seem to have some "memory" of its original shape. If you heat it up again, it tends to return to the way it was.
I imagine the original shape was a liquid mass of goo, but the first time it is shaped is as pipe. If you just soften it to stretch it, heat it again and it unstretches.
Someone at the PVC factory told me once that they never have any 2nd quality pipe, because if it is defective, they just reprocess it. From that, I imagine that you can take solidified PVC and melt it again, probably in the absence of oxygen.
You can weld it somehow with a hot air gun and a special tip, but I never had any luck with that.
I don't know the science behind it too, but plastics tend to have a memory of the shape they were in before...
There was a video on youtube that showed someone heating a yoghurt cup in an oven and it returned to the disk like shape they melt to form the cups...
Wikipedia also mentions that it's a thermoplastic.
As I recall, the idea was to stick the PVC pipe up the exhaust pipe and gradually bend it, making the angle appear at the end of the exhaust pipe.
Years ago, I read of some Boy Scout leader who built a little oven around the exhaust pipe. They put food in at the beginning of a trip and it was ready when they arrived. Seems like it would have to be gas tight to avoid contamination of the food. Anyway, it seems like a creative use for exhaust heat.
It was common, when I was in the field, to put your laundry in a big metal ammo can, with soap & water, and then strap it to the intake manifold. As you drove around, it heated the soapy water & agitated it like crazy, so all you had to do when you got back was rinse the stuff. The process had a lot of cute names like "Military Maytag," etc.
No sense wasting heat ....
Thanks!
I have been doing that with masts that I use for Radio Antennas for many years and with 2 coats of white paint I have only had one break in 5 years due to sun / wind damage.
The wind sandblasted the paint off about 15 feet up and I didn't see it.
Good luck on the greenhouse and post an instructable on it.
Also, do you think it would work on the thicker walled cpvc?
CPVC does heat form, but it takes more heat than PVC.
Hopefully, as long as I don't get to distracted by shiny objects ;)
Anyway, yes, it is possible to make seats with PVC. Making comfortable and good looking ones is the trick.
They used custom slings to hold the cushions at an angle instead of the chair backs being straight. We still have a table or 2 kicking around the yard!
Nice Instructable!
I wish I would have seen this before my hip surgery, I made my cane from straight pipe and some fittings. It's not as slick looking as yours, but it also has a hidden lightsaber :)
Is it possible to bend 32 or 40 mm pipe using this idea.
Thanks
See: http://www.youtube.com/watch?v=iV-CE3hW4ss
Using sand to maintain the id of the pipe is excellent! We used to wrap the pipe with aluminum foil and use a butane torch to heat it up. The foil helped distribute the heat evenly over the bend and kept the pipe from getting too hot in one place and catching fire. The Pipe Viper is awesome, but it's always nice to know techniques that work without specialty tools. Thanks for the post and the excellent idea!
Plumbers should use this method... they could keep a supply of curve pipes for future tasks.
But, this idea for bending PVC is a good instructable and, the resulting stable shapes are likely to be most useful for other projects where the rigid result is desired "after the bending."
Nice tip Thinkenstein
One question though . If youre married and making something for
the home the lady of the house obviuosly wants it more refined .
Any tips on that.? For example smooth edges maybe some colour
staighter edges etc
Thanks
Alternative solution: help women to evolve to appreciate less refined things. Preferably, teach them to make the things themselves. Leave the edges and color up to them.
If it works like I remember I'll post a picture and maybe make an 'ible of my own about it.
Anyway, whatever you remember seems new to me, and I'd like to know what it is.
its like a long spring, one of those pull versions, it fits really nice inside, and it doesnt require alot of force!
I asked my dad about it and he says that it works with all "normal" PVC pipe of normal diameter.
Just stick the spring in there and bend using your hands. I can't find the spring in the garage right now but if I can't find it in the morning I'll search for a picture on google :)
There ya go, it was quickly found. This is what we used in school. A spring that bends the pvc pipe cold without compromising the integrity or durability of the pvc pipe also the spring is the same diameter as the innerhole so while bending the hole won't get smaller.
This video explains how it works and how less time consuming it is.
According to me it has been around for atleast 4-5 years since I came in to contact with it when I was 14.
That's why it suprised me nobody here seemed to realize you could bend pvc cold. Well this is were instructables is for gaining knowledge and using it to fit your needs :D
This video should give you a pretty clear picture.
But it's just sticking the spring in. Look were you want to bend your pipe. And bend it with your hands until you have the shape you want. Then you just pull the spring out and your done :D It does require the use of some force but if a 14 year old can handle it I'm pretty sure everyone here can too.
I have bending springs for copper pipe but had not realised that it would work for PVC pipe without heat.
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In the first usage it seems to have been generalized to refer to the entire exhaust manifold unit from the exhaust ports to the exhaust pipe. In the second usage it means any individual pipe that is connected to the exhaust manifold to direct the exhaust gasses, even if (as in your example) it doesn't even connect to a collecting manifold or exhaust pipe. Whether the header is mostly designed to enhance looks or performance doesn't seem to matter.
I think the technique was probably used in copper pipe bending before PVC was invented. I've never done it, but I feel pretty sure it would work.
www.thepipeviper.com/aseasyas123.html
Do you think this compromises the structural intergrity of the pipe?
Nonetheless I've always wondered if bending PVC was possible, hell I'm not paying to by useless joints any longer. Good to know! Great Instructable!
Theater props? Sounds like fun.
When I was creating one of the Jack Skellington Puppets, I had a hard time rounding the PVC, and made slight incisions to make it flexible. I wish I had known this method then! It would have saved me hours.