I've been heating and reusing the copper washers on oilfill plugs for 
years.  I used to be a goldsmith, did alot of model making in copper.  
Copper gets brittle when worked and requires annealing by heat to make it 
soft again.  As you continually reheat and reuse (i.e. reharden) the 
metal it will start to get flatter and wider.  After 3 or 4 times you'd 
be better off replacing the wAsher with a new one.

--
evan e.
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 > From vanagon@lenti.med.umn.edu  Mon Oct 17 13:13:46 1994
 > Date: Mon, 17 Oct 94 15:13:11 CDT
 > Errors-To: gsker@lenti.med.umn.edu
 > Reply-To: vanagon@lenti.med.umn.edu
 > Originator: vanagon@lenti.med.umn.edu
 > Sender: vanagon@lenti.med.umn.edu
 > From: Richard Lamoreaux <riclam@deety.radiology.arizona.edu>
 > To: Multiple recipients of list <vanagon@lenti.med.umn.edu>
 > Subject: Re: copper washers??
 > X-Listprocessor-Version: 6.0c -- ListProcessor by Anastasios Kotsikonas
 >
 > Joel wrote:
 > > get kinda flattened tooo much, a porsche mechanic showed me a neat trick:
 > > get a propane torch and heat them up until they (washers) are red hot, then
 > > let them cool off somewhere. it 'fluffs' the washers back up. and i figure
 > > if it's good enough for his 911's, it's good enough for my vanagon. :)
 >
 > I used to do this to my copper head gaskets on my Yamaha 2-stroke 
 > motorcycle. But I always read that you should quench the red-hot copper 
 > in cold water to make it soft (as opposed to steel, where it makes it 
 > harder). It seemed to work well for me.
 >
 > Richard Lamoreaux      
 > (602)626-7576
 > riclvw@deety.Radiology.Arizona.EDU
 > University of Arizona
 >
 > '78 Chicken coop
 > '87 weekender
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