Does a butane torch get hot enough to anneal copper?

[Tobra]

Have some washers for the oil drain. Cleaned them up with steel wool, hit them with a butane torch for about 30 s and quenched them. Are they annealed, or does it need a hotter fire?

[nota]

anneal means cool slow NO WATER QUENCH

copper needs it ?
it is soft from the start

[nota]

you just tempered it

but why?

[javadog]

Yes, butane burns hot enough to anneal copper. It’s hard to say if you heated it enough, it needs to get to a red hot stage. Immediate water quenching is fine.

[Jim2]

Propane works fine on those copper crush washers. Not sure of the temp required but I usually heat them just until the flame turns slightly green then let the washers air cool (toss them on my vice). They will be soft again.

[911boost]

I’ve read you can on the Samba as it relates the copper exhaust gaskets.

[wdfifteen]

Originally Posted by javadog

Yes, butane burns hot enough to anneal copper. It’s hard to say if you heated it enough, it needs to get to a red hot stage. Immediate water quenching is fine.

Red hot is plenty. Do not quench! I heat a steel plate and put them on it. Heat them to dull red and walk away until they are cooled. Metals need to cool slowly to be annealed.

[javadog]

Originally Posted by wdfifteen

Red hot is plenty. Do not quench! I heat them to dull red on a steel plate and walk away until they are cooled. Metals need to cool slowly to be annealed.

That seems to be the general wisdom but it does not hold true for all metals.

[Shaun @ Tru6]

I buy a lot of steel and aluminum from these guys and they always have good educational videos

What’s the difference between annealing and tempering?

[dad911]

Why? Are you re-using old ones?

[RAM]

Assuming this is copper and not an alloy, the idea is to stress relieve rather than anneal. If this is copper and the alloy, if an alloy, does not contain Al then cooling after heating will have minimal affect. The specific heat needed to either stress relieve or anneal will depend on the copper or alloy. I have a book on heat treating Cu and Cu alloys if needed.

In my opinion, too much work, time, and cost to either stress relieve or anneal compared to buying a new washer.

I assume we are talking about a copper washer for the oil drain plug on a 911.

[sammyg2]

Originally Posted by nota

you just tempered it

but why?

There is a big difference between copper and carbon steel. Big.
What you described applies to steel but not to copper.




To anneal copper: heat it cherry red, and drop in bucket of water or air cool.

https://www.wikihow.com/Anneal-Copper

[John Rogers]

Way back in the day when we had our pair of 914s and our 1973 VW Bus with the 1.7L engine, the factory and also our shop in San Diego said to never reuse the header copper header gaskets. They said to always use new seal gaskets when putting the headers back on. So I tried annealing the gaskets on the bus to show how smart I was....so in about a week two of the four exhaust flanges started to lead!

[Tobra]

Yeah, oil drain washer, seems a waste to discard them. It was hot enough to change color in less than a minute, not sure I would try it on copper head gaskets though