Author Topic: Soldering copper  (Read 2831 times)

Offline Mike K

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Soldering copper
« on: June 24, 2021, 11:23:02 AM »
How reasonable is it to construct a box out of flattened copper plumbing tubing and joined with plumbing solder?  It won't hold pressure, but I do want it to keep out rain.  Is the use of silver solder just for pressure applications?

Offline Sea.dog

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Re: Soldering copper
« Reply #1 on: June 24, 2021, 11:46:50 AM »
If that's all that you have, then use it. Soft solder will be fine and need a lot less heat. Make sure that you use lap joints or, if you've enough metal, folded lap joints.

Offline Mike K

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Re: Soldering copper
« Reply #2 on: June 24, 2021, 06:37:20 PM »
Oh, I was just going to do 90* butt joints.  No good?  I don't have a sheet metal brake.

Offline awemawson

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Re: Soldering copper
« Reply #3 on: June 25, 2021, 02:38:03 AM »
It’s all about surface area of the joint.

Conventionally copper ware joints would be castellated like a box joint if laps or folds weren’t possible.
Andrew Mawson
East Sussex

Offline Sea.dog

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Re: Soldering copper
« Reply #4 on: June 25, 2021, 05:45:34 AM »
Since I've no idea of the intended use or size of the piece, I can't say whether or not a butt might work.

Offline mattinker

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Re: Soldering copper
« Reply #5 on: June 25, 2021, 06:09:51 AM »
Mike,

Water pipe copper will bend nicely in a vice, if it's longer than the vice jaws, a couple of smooth pieces of angle iron to extend. Hammer to form angle. Soft solder will be more than adequate for a rain cover. Anneal before cutting by heating red hot, quench in water of air cool.

Cheers, Matthew

Offline ddmckee54

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Re: Soldering copper
« Reply #6 on: June 25, 2021, 10:15:18 AM »
I second what Matthew said.  Just be sure all mating surfaces are clean, clean, clean!  Did I mention that everything needs to be clean?

Don
Too many irons, not enough fire.

Offline Mike K

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Re: Soldering copper
« Reply #7 on: June 25, 2021, 07:52:28 PM »
Okay, I'll give it a shot.  Pieces, by the way, are 2" x 4" and joined along the 4" to form a rectangular tube with something to be fitted to the top and bottom.