Date:         Fri, 8 Apr 2005 00:21:54 +1200
Reply-To:     Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Subject:      Re: working copper tube
In-Reply-To:  <000c01c53b32$a8091be0$c9edf004@computer>
Content-type: text/plain; format=flowed; charset=us-ascii

>I am finally finishing a too long project to add a second propane
>tank to my '90
>Westy, and have a question for the metallurgists (or anyone who
>knows) on the list.
>Yesterday I bought some 3/8" O.D. copper tubing to connect the two
>tanks, and while
>the clerk was coiling it up very carefully, he said you don't want
>to work it too much
>because it causes it to harden. He called it "work hardening". True or false??
>Thanks,
>Jerry

Yes. It's correctly called "metal fatigue" Copper is decidedly prone
to this. You can minimize it by heating the bits to be bent til they
glow red, then dipping them in cold water; this anneals them, and
they will be soft and malleable.
--
Andrew Grebneff
Dunedin
New Zealand
Fossil preparator
<andrew.grebneff@stonebow.otago.ac.nz>
Seashell, Macintosh, VW/Toyota van nut

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