# Need help bending copper pipe



## Lux Luthor (Oct 13, 2004)

I need to make a coil from some 1/2" copper pipe. This is the standard hollow stuff used for plumbing. Will heating it with a torch do the trick, or will it still get kinked?


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## BIGIRON (Oct 13, 2004)

Two basic kinds of common copper -- rigid and "soft". Would be very difficult to coil the rigid type. If you don't need the coils in too small a diameter, a bending spring (literally a steel spring about 18" long that the copper fits inside) will work fine for the soft copper. A set of 1/4, 3/8, 1/2 and 3/4 shold be available for under $20.

A plier type tubing bender will be available at an auto supply store. I've never been able to get one to work 100%. I generally wind up flattening at least one bend.


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## McGizmo (Oct 13, 2004)

I have not tried it myself as I have been successful with hickeys (sp) and tube benders but I understand if you fill the copper pipe with sand, it will be less prone to kink while bending. /ubbthreads/images/graemlins/icon3.gif


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## tvodrd (Oct 13, 2004)

McGizmo _pounding sand-_ I love it! /ubbthreads/images/graemlins/crackup.gif /ubbthreads/images/graemlins/nana.gif BIGIRON been there-(obviously)done that. The ridgid stuff can be bent into about a 6" radius, but finding a tool to do it will be a challenge! The (AFAIK) hand tool$ don't go up to 1/2" trade size. The (over)spring process leaves a lot to be desired, in my experience! Commercial benders require diameter-specific wheels, and LuxL, sorry, but I think you are on your own here. Wish I could help.

Larry


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## d'mo (Oct 14, 2004)

If sand won't do the trick, I've been successful filling copper pipe with solder. Bends great. Then reheat to melt the solder back out. Probably not all that great for drinking (lead content), but for anything else it should be fine.


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## cosco (Oct 14, 2004)

Are you going to distil something or what? /ubbthreads/images/graemlins/grin.gif


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## rdshores (Oct 14, 2004)

I have used V groove pulleys off a car waterpump or power steering pump to bend copper tubing around. Work good if you hold the tubing tight into the groove.


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## mahoney (Oct 14, 2004)

The soft copper tubing used in refrigeration, HVAC, etc. comes in coils about 1 foot in diameter. It's not too hard to gently persuade it into coils a few inches smaller in diameter, especially if you have a proper size cylinder to form it around. If you need a really tight coil, find a shop that specializes in tube bending and they will have the tools to do it without kinking it.


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## wasabe64 (Oct 14, 2004)

rdshore's suggestion makes sense, the groove walls will support the 'flanks' of the pipe to prevent kinking. You just have to find the right sized pulley. /ubbthreads/images/graemlins/grin.gif

Can you get away with using the bendable copper tubing instead of the rigid pipe? 

That option can spare you from a lot of running around and the added cost of tooling.


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## tvodrd (Oct 14, 2004)

The ridgid stuff can be annealed by heating it "cherry red," and quenching it in water. /ubbthreads/images/graemlins/icon3.gif (Same for common brass alloys.)

Larry


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## Lux Luthor (Oct 15, 2004)

[ QUOTE ]
*cosco said:*
Are you going to distil something or what? /ubbthreads/images/graemlins/grin.gif 

[/ QUOTE ]

That would certainly cut down on my drinking expenditures. /ubbthreads/images/graemlins/grin.gif

But no, this is for heating water to take a shower with during a winter power outage. I've had to do this before, and had to resort to some really awkward solutions.

I want to just lay this coil on a propane stove, and run one line to my waterpik. I know about CO and oxygen depletion, and no one will convince me I'm going to die if I leave the door open and run the thing for 15 minutes. /ubbthreads/images/graemlins/smile.gif

That HVAC stuff sounds like the easiest approach, but can you get it in 1/2" size? I need atleast reasonable water pressure.


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## red_robby (Oct 15, 2004)

someone already said this...a EMT(electrical metal tubing) pipe bender(hickey)will bend copper pipe, no problem.
they come in 1/2", 3/4", 1", 1 1/4", and 1 1/2".


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## mahoney (Oct 15, 2004)

The soft copper comes in 1/2", although it's sized by OD so you might want to go up to 5/8" if you need a 1/2" ID. 5/8" will be a mite harder to form. Temperature regulation will be a factor of flow and heat output at the stove and may be tricky. 

Interesting project, I think I'd be tempted to go much lower tech, maybe a galvanized watering can with a sprinkler nozzle heating on the stove.


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## Lux Luthor (Oct 16, 2004)

Thanks.

A watering can would be fine, but you need to hold it high enough or pump the water out. In the past, I've hung 5 gallon water carriers from the ceiling (which was a PIA), and more recently resorted to a pump. It would be nice, though, to be able to use the preexisting water pressure. With a pump, you need to heat the water first, and it takes a long time.


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## mahoney (Oct 20, 2004)

It's still going to take just as long to heat the same amount of water either in the coil or in a can, assuming the same stove. Of course you'll be showering while it heats with the coil. Given the amount of effort you've put into this in the past, it's worth a try, but the flow rate through the coil necessary for the water to heat to an acceptable temperature may be too slow for an acceptable shower. 
It sounds like this is a re-occuring problem. Probably out of the question to change over your water heater to gas or propane?


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## Lux Luthor (Oct 20, 2004)

What I was doing was heating water in a pan on a propane stove, then dumping it in a pail. I think there's a lot of heat wasted while the water is being heated in the pan, and also while it sits in the pail waiting for the next pan of hot water. I did get a California Innovations cooler that has this stuff called thermaflect. I replaced the pail with it, and it helped a little.

You may still be right, though. I am definitely concerned about being able to heat the water fast enough. I figure I could start with one coil and see what happens. If I need to use a 2 burner stove with some sort of double coil, and/or use higher output burners, I'm willing to go with that too.

As far as switching to propane or gas, I rent, so that's not an option.


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## mahoney (Oct 22, 2004)

There might be an easier solution. Take a look at "instant" or "tankless" gas water heaters. I know these are available for residences, smaller versions may be available for RVs and boats too. They are designed to heat water fast enough for a shower, some do not require any electricity to work, and you can get propane fired models. With a 20 lb propane tank and a vent pipe out the window you could be set. The heater will probably cost a few hundred dollars but if you end up needing double coils on a bigger camp stove, etc., you might spend almost as much. And the heater will heat water more efficiently than the coils on the camp stove, which will save you money on propane in the long run.


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## Lynx_Arc (Oct 22, 2004)

I wonder if pulling a thick flexible cable of wire a little smaller than the Inside Diameter through the pipe would allow you to bend it without the sides collapsing and kinking. It should maintain the integrity of the walls of the copper tubing and you could pull it out when you are done. If it gets stuck maybe you could pull a few wires at a time.


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## theepdinker (Oct 22, 2004)

Lux,
Ebay- category, sporting goods-camping,hiking,backpacking
search, shower
Check out anything made by Zodi.
I own their single propane bottle shower & use it in deer camp.

Theepdinker


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## Marked (Oct 26, 2004)

"Thin wall metal tubing can be successfully bent without the usual distortion when filled with a low melting alloy. The tube then bends as if it were a solid bar, and the alloy can be melted out in hot water and collected for re-use."
Bismuth Alloys
http://www.smallparts.com/products/descriptions/LMA.cfm


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## Lux Luthor (Oct 26, 2004)

I found some of that coiled soft copper stuff at Home Depot. It bends easily enough, but I couldn't bent it into a tight coil without kinking it. You can bend it a fair amount, though, just not a huge amount.

Also, thanks for the zodi link. In looking at their products, I may decide to go with something more robust than what I had originally planned. During the last ice storm I was in, the lack of hot water for washing dishes also became an issue after a couple of days. So it might be better in the long run to just get a dedicated hot water unit.


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## turbodog (Oct 26, 2004)

If you don't lose electricity, go with an instant water heater. I have 3 of them myself. You can get a single sink/shower/point-of-use model for about $300. It will heat about 1.5-2 gallons per minute at a 60 or so degree temp rise. This is with 40 amp 240 volt input. 

Ask me about running wire for the 120 amp 240 volt model!


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## NamTinker (Oct 26, 2004)

Lux
You could also try the bismuth-type low melting point metal available from (for instance) Small Parts Inc. Two types - most expensive type melts at around 40 degrees C, so you can use boiling/hot water. Fill up the pipes, bend, put in hot water to remove. Have used it to bend some s/s cannon barrels for R/C model warships. Works well, expensive for one-off type operation though.


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## Ken_McE (Oct 29, 2004)

*Don\'t need To Bend*

Soldering copper is easy. You could buy a lot of fittings and just make a pieces of pipe that zig zags along next to itself.


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