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Harley fan needs backyard process to anneal copper gaskets

I am curious about the copper annealing process. I am trying to fabricate a gasket for the exhaust pipes on my 53 Harley. I believe copper would withstand the heat range I am looking for, but copper in its natural state is not malleable enough to conform into the shape I need. Therefore annealing may be the process to make the copper more workable for me. I just need to know the backyard annealing process for copper.

Thank you,

Kevin Adriance
hobbyist/harley enthusiast - Galway, New York
2003

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I'm sure that annealed copper gasket sheeting is available, but just heating what you have to a dull red should remove the cold working and make it soft for use as a gasket too.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

You may find the copper you need sold as dead soft or annealed. It is available but not particularly easy to find. Copper is backwards to steel in annealing. You take it to red hot and then plunge it into a bucket of water. You slow cool it to harden it. A warning, You will have lots of scale from the heating process unless it is done in an inert atmosphere, which virtually no one has.

James Watts
- Navarre, Florida
2003

It is possible to anneal copper at home but you need to get the copper to at least 800°F to start the process. Use a torch and get it as hot as possible and then water quench. Oxidation scale is a certainty but that may not matter to you. We use an inert furnace at over 1100°F with a long heat up and cool down. The finished material looks exactly the same just soft.

Pat Wilkerson
- Illinois
2004

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To prevent oxidation during annealing you could coat it with a protective material such as Scalex.

Albion Zeglin
- Montgomery Village, Maryland
2004

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2005

I want to anneal copper washers to maximum 40 HB. Please suggest the suitable process for it. I have tried doing the same using the process like blow lamp & conventional oven but I am not able achieve the consistency in the hardness.
Mr. Pat Wilkerson - IL has answered the query on 28-1-2004 & he could suggest some other methods.
Thanks,

Shashank Shetiya
- Mumbai, India

I have done a lot of work with a large vacuum furnace where I have done vacuum brazing and have annealed a hundreds of pounds of copper. In my experience a slow cool in my vacuum furnace worked very well.

Richard Anderson
- Fort Collins, Colorado
September 11, 2009