Bending 1/2" copper tubing into circle


  #1  
Old 08-01-04, 09:15 AM
rainbowsoup
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Question Bending 1/2" copper tubing into circle

undefined Good Morning. I'm new to your site and am an artist attempting to bend 1/2" copper tubing into a large circle. It needs to be visually correct. Right now, I have an egg shaped looking thing. I've been searching on the net and find conduit benders etc., I'm just looking to bend the copper into a circle and sodering it together. Right now, I'm looking at a sledge hammer and am considering beating it into submission. This site is great and I look forward to your help. Thanks in advance. Signed: A frustrated artist in Phoenix.
 
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Old 08-01-04, 08:03 PM
scrapiron
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You don't say how big a hoop you're looking to make. I would find (or make) something I could wrap the copper around that is approximately the size you desire. I would crimp one end of the copper shut, fill it with sand and crimp the other end shut. Start with a piece of copper several inches longer than the finished piece, clamp one end to your pattern and wrap it around. Cut the ends off, shake the sand out and solder the ends together. Good Luck!
 
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Old 08-01-04, 08:20 PM
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Welcome!

rainbowsoup,

First off you need to use soft drawn tubing and not straight pipe.

Like scrapiron suggested locate a round object that is the same diameter as the circle you wish to have.
Wrap the soft tubing around the object and keep bending past the point where the two ends meet.
Then cut through both pieces at the same time and the two ends will join.

How large a circle are you trying to make?
 
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Old 08-02-04, 07:13 AM
rainbowsoup
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Circle is 22" in diameter

Thanks for your feedback my friends! Well the circle is 22" in diameter. I've been playing with it, it still is not visually round. I'm going to reread your posts and assimilate the info. You experts would know this...isn't there some kind of jig that you can feed the tubing through to straighten out the kinks? Ah yes, those artists can drive you crazy. Thanks!
 
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Old 08-02-04, 07:22 AM
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No, there is no way to get the kinks out.
If I put an unnaceptable kink in a tube it gets put in a scrap bin to sell and replenish the xmas refreshments.

If you use soft drawn which is tubing that is sold in a roll it should not kink if you use something to bend it against.
22" is almost the diameter of a 20 lb propane tank.

Take the straight piece of tubing and carefully bend it around the tank not stopping untill the tubing starts to make a second go round and is round where you will cut it.

If you have a plentifull supply of hard drawn plumbers pipe you can remove some of the temper by heating it to cherry red.
You only then have to polish it up.
 
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Old 08-02-04, 01:55 PM
Yggdrasil
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There's a tool called a "ring roller" which would work perfectly for your 22" hoop. Unfortunately I don't have a picture of the one in my garage, but a simple google search should hook you up. I suspect once you've seen one, you can easily make one and then you've got unlimited hooping ability.
 
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Old 08-02-04, 02:14 PM
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Just wanted to add, the object you bend the tubing around need not be exactly 22". You just need to get close to the final diameter, then push or pull the ends together to force the piece to the size you want.

Too small is better than too large, since then the ends can push against each other to hold the piece at the correct size while you do the final soldering. If the piece is too large, you need to have some sort of clamp or fastener to keep the ends from spreading farther apart.
 
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Old 05-03-09, 02:47 AM
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same question found lil help

same question found lil help other than bend over somthing round.. guess obvious answers are to be expected, however in experimenting with the tubing i found a ruber mallet helped when i got kinks in the curves. also i found that placing a plastic or better a metal tomato stake inside the pipe while bending made thing alot easier and smooth. i used a MAP gas torch and a few stubborn parts but i wouldnt recommend cus it changed the color but it did soften up the metal,,anyway had to mention that wouldnt forgive myself.. hope it helps, jace
 
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Old 05-03-09, 05:17 AM
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bending rigid tube requires a double mandrel bender. not a cheap tool. you might try an exaust shop or race car chassis fabricator.
 
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Old 08-14-09, 01:17 PM
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Hi all I just wanted to share with u my project. I had to bend a small copper pipe (2 actually one was a bit larger) but they were attached on one end to my AC so packing sand/salt into the tubing tight enough to work was out of the question. Instead I used electrical wire (comes in many different gauges) wound several tighley together if I needed the diameter to be larger (also left the plastic sheathing on the wire and sprayed w/WD40) inserted it into the the tubing and it worked like a charm. Hope this helps. Beer 4U2
 
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Old 08-14-09, 02:06 PM
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Thanks for sharing.

Your method might be ok for some applications but a/c tubing must be spotless inside.
The WD-40 would most certainly help with the bend but the residue left inside the pipe is a contaminant that will likely shorten the life of the compressor.
 
 

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