Many of our old engines use copper gaskets, particularly when you have a removable cylinder (eg. Lister diesels and petrol engines, Southern Cross Engines, and many others). The copper gaskets are used as both shims and seals to between the crank case and the cylinder. Some engines used copper for head gaskets (I have a Rosebery 3C vertical which has a copper head gasket). The copper gaskets can be reused but need to be softened (or annealed) first. The question came up on the SEL and had the following helpful responses...

This email address is being protected from spambots. You need JavaScript enabled to view it. asked:
Hi gang,
What's the best way to make old copper (sheet) soft again?
We made a copper gasket ring for our Wichterle from an old sheet but want to
make it softer.


Harry Terpstra
Sint Anna Parochie
Netherlands
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This email address is being protected from spambots. You need JavaScript enabled to view it. responded:
I've been told to heat it and quench it..opposite of steel...called
annealing I think. If once isn't enought do it again.
Rick
This email address is being protected from spambots. You need JavaScript enabled to view it. added:
In annealing of copper, the heating is the important part. The rate of
cooling is immaterial.

Whether you allow it to cool naturally or drop it into water makes no
difference to the final softness.
.
Traditionally, we drop it into water because that's what we were told, but
it is not necessary. It's only a matter of convenience

Try it both ways and see for yourself.

JW²
Perth W.A. Oz
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This email address is being protected from spambots. You need JavaScript enabled to view it. added similar:
    Heat it to a dull red and quench it.

Bob Willman
The Eagle's Anvil
Bowling Green, Ohio
WB8NQW

And same from This email address is being protected from spambots. You need JavaScript enabled to view it.:
Anneal it by heating to cherry red and dumping it in a bucket of cold water.

This email address is being protected from spambots. You need JavaScript enabled to view it. added some very handy advice:

Drop it 'edge-on' into cold water, otherwise you'll get covered in scalding
water...
Peter

This email address is being protected from spambots. You need JavaScript enabled to view it. agreed with the others...
To anneal any non-ferrous metal you heat it up and plunge it into water

Clarke L. McGee

A:

In annealing of copper, the heating is the important part. The rate of
cooling is immaterial.

Whether you allow it to cool naturally or drop it into water makes no
difference to the final softness.
.
Traditionally, we drop it into water because that's what we were told, but
it is not necessary.  It's only a matter of convenience

Try it both ways and see for yourself.

JW²
Perth W.A. Oz
This email address is being protected from spambots. You need JavaScript enabled to view it.

A:

Good on ya Jack .I was wondering when sombody would say that.You only cool
it so you can handle it.
EDD PAYNE
PO BOX 364 GULGONG
New South Wales  AUSTRALIA
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