Processing Copper Wire - Burning The Wire 1

[Mac In Oak Ridge]

In this post I'll explain how I anneal the wire in a small wood fire in the back yard. This is where we are headed:

In the photo there are four rolls of #6, #12, #14, three rolls of #16 and four rolls of #18, shown left to right. This is the finished product.

Rolls put on the fire:

As the rolls heat up they start getting orange and then transition to a black color. The color changes as the surface oxidation reacts to the temperature of the copper and it's alloys. In this photo you can see the black areas and the areas turning orange.


While this is going on I turn the coils over with a long stick in order to even out the heat in the coils.

As the heat increases the black starts fading and the copper becomes a golden color, likely the oxidation of the brass content of the copper.



In these two photos you can see the gold color developing on the copper. This is just before the copper reaches the fully annealed state. I continue to flop the coils over every two or three minutes to even out the heat and I also move them to hotter parts of the fire bed if I see that an area is not getting the heat to continue the process.

More in next post

 

[Mac In Oak Ridge]

Processing Copper Wire - Burning The Wire 2

As the heat in the copper continues to build the gold or brass color starts turning a reddish color that quickly goes to a black color with a copper color tint:



I leave the coils in the fire at this point for an additional two or three minutes to make sure that the interior of the coil gets a chance to reach the full temperature.

Then the coils are taken out of the fire and laid on the ground beside it. When I have finished putting all the coils through the process I pour cold water on them so no one burns their hands.



If you have anyone working with you, especially children, tell them not to touch the coils until you have touched them yourself. And don't you touch until they have been cooled down with water or let sit for an hour or so. Copper will hold heat for a good while.

You are done and have quite usable wire for bonsai at this point. I mark each coil with the size so I can quickly retrieve what I want from my stash.

Copper melts at about 2000°F. You don't need to worry about getting it that hot in a wood fire unless the single strands get loose and you go to sleep and don't notice it. It anneals at about 1300°F, an obvious large difference between annealing and melting.

Forget needing to get it red hot to anneal. Folks confuse annealing steel with annealing copper sometimes. It doesn't hurt to drive for the temperature that copper does get red hot but it matters not as long as you get past the golden color oxidation and into the orange/black oxidation that shows just past the gold color point.

And it is not necessary to plunge the copper in water to fix the anneal. They can cool down naturally or have water poured on them immediately and it makes no difference. I pour water on them so I can handle them more quickly. Some coils have sat there for 20min. or more and some just out of the fire when the water hits them. Some confuse the copper annealing process with annealing steel to a given hardness.

The key to making this process worthwhile is getting the copper wire you want to use at a cheap price. If you pay the same price for un-annealed wire or close to the same as the annealed wire it is a pointless exercise if you value your time. I did pay too much for the wire used, except the #6, for this exercise and would have come out at about the same price as if I had bought the wire from a well known supplier of bonsai gear that has a sale going right now. However I keep my eye out for wire at good prices and know that when I find it I can convert it for bonsai use. As in the previous post states you can burn the insulation off the wire should that be the wire that comes your way.

If I weren't taking photos I would say it takes about 10 min. to process three coils of copper at one time in the size of the fire I build. Larger diameter wire and larger coils with more copper in them would take a little longer to reach temperature.

Happy to answer any questions. And keep in mind, this is the way I do it. Doesn't make it the only way to do it. A charcoal grill would work, if you use charcoal it will be a much hotter fire and require closer attention. There would be a chance of melting your wire with charcoal. Any kind of propane burner, grill, fish or turkey cooker burner will produce heat. Only one or two coils and a hand held torch likely would do as long as you get the even heat all the way around your wire coil.

 

[jkd2572]

Thanks for giving us the temps. I was thinking about trying this on my gas grill, but I don't think it could get up to 1300 degrees.

 

[yenling83]

This is really great, I appreciate all the info you shared! Yes, finding copper wire from a good inexpensive source is the key. If anyone runs into a great supplier I'd love to hear about it. I'm sure there is some website that has it at good prices, but I have not been able to find it.


I wonder how soft your wire get's compared to the current wire I use which is annealed by Jim Gremel? I would like to try both and compare. thanks!

 

[Smoke]

By quinching your wire after heating is defeating the purpose. Bringing any metal up to temp to anneal it and then quinching tempers the metal. Bring it to temp and then allow it to cool slowly will keep it nice and soft.

 

[Poink88]

By quinching your wire after heating is defeating the purpose. Bringing any metal up to temp to anneal it and then quinching tempers the metal. Bring it to temp and then allow it to cool slowly will keep it nice and soft.

This is true for steel but supposedly not for copper.

 

[lordy]

I will repeat, I use a gas grill and do not use a thermometer, I just watch the color of the wire. When it starts to show ash or black color, or better yet, red hot, I turn off the gas and let it cool. Even in smallish coils, this wire is plenty soft to wire trees with. It may BEGIN to harden after winding most of a branch, but not to the point it is unusable due to being too stiff.

 

[berobinson82]

I once asked Julian how he annealed his copper. He told me he'd divulge his method when he was ready to retire. There is a lot of conflicting information on this subject. Add it to the list I suppose.

 

[jkd2572]

I guess I will keep buying from Jim Gremel until I figure it out.
http://www.jimgremel.com/copperwire2106.html

 

[Smoke]

This is true for steel but supposedly not for copper.

I have been using copper wire for 30 years. Copper wire should even be annealed yearly or at least every other year. Just the difference between winter and summer will work harden copper. Kenji Miyata will bust your knuckles if you pick up a roll of wire with one hand or allow it to clunk on the table.

I don't care what anyone says if you quench copper you change the arrangement. Change the arrangement and it hardens.

Also the rolls of wire being shown here are much too small. They should be at least 12 inches in diameter over 14 gauge. 5.5 inches is too small and even trying to use a 5.5 coil for a tree will harden just making it straighter and usable for winding around a branch.

To really do copper correctly, it should be cut in two or three foot lengths, annealed straight and stored in tubes. The tubes protect the copper from damage and it is ready to use straight from the tube.

 

[Poink88]

I don't care what anyone says if you quench copper you change the arrangement. Change the arrangement and it hardens.

All of these are wrong then.

http://www.inlandbonsai.com/articles/copper/copper.pdf - by Marty Weiser
http://www.evergreengardenworks.com/copperwi.htm

http://www.evergreengardenworks.com/copperwi2.htm

http://www.materialseducation.org/e...cs/Work_Hardening_and_Annealing_of_Copper.pdf

http://en.wikipedia.org/wiki/Annealing_(metallurgy)

http://mrooker.com/JMUmetals/technical/Annealing.html

 

[Smoke]

All of these are wrong then.

http://www.inlandbonsai.com/articles/copper/copper.pdf - by Marty Weiser
http://www.evergreengardenworks.com/copperwi.htm

http://www.evergreengardenworks.com/copperwi2.htm

http://www.materialseducation.org/e...cs/Work_Hardening_and_Annealing_of_Copper.pdf

http://en.wikipedia.org/wiki/Annealing_(metallurgy)

http://mrooker.com/JMUmetals/technical/Annealing.html

I guess you won't know until you try it.

 

[Poink88]

I guess you won't know until you try it.

I know...your standard reply to anyone with less experience than you. That's fine, message is delivered to the rest. They can read the links and hopefully make an intelligent decision/choice.

Thank you.

 

[Ris]

Thanks for the links Dario.

 

[Mac In Oak Ridge]

By quinching your wire after heating is defeating the purpose. Bringing any metal up to temp to anneal it and then quinching tempers the metal. Bring it to temp and then allow it to cool slowly will keep it nice and soft.

You are incorrect in your statement and apparently don't know about counteracting work hardening of copper and copper alloys.

 

[Beng]

I have been using copper wire for 30 years. Copper wire should even be annealed yearly or at least every other year. Just the difference between winter and summer will work harden copper. Kenji Miyata will bust your knuckles if you pick up a roll of wire with one hand or allow it to clunk on the table.

I don't care what anyone says if you quench copper you change the arrangement. Change the arrangement and it hardens.

Also the rolls of wire being shown here are much too small. They should be at least 12 inches in diameter over 14 gauge. 5.5 inches is too small and even trying to use a 5.5 coil for a tree will harden just making it straighter and usable for winding around a branch.

To really do copper correctly, it should be cut in two or three foot lengths, annealed straight and stored in tubes. The tubes protect the copper from damage and it is ready to use straight from the tube.

Smoke I really like this straight strand idea!!! Why should we have to unbend a roll if it changes the composition of the copper by doing so. Thus reducing the effectiveness of the annealing process. But who sells copper like this, I've never seen if anywhere? If I had I would have bought it.

 

[berobinson82]

Smoke I really like this straight strand idea!!! Why should we have to unbend a roll if it changes the composition of the copper by doing so. Thus reducing the effectiveness of the annealing process. But who sells copper like this, I've never seen if anywhere? If I had I would have bought it.

I too like the idea of straight storage. In my imagination, vendors don't sell it in tubes because of the ease of shipping the rolls.

I wonder if someone who has only been wiring, say, 5 years, would even notice the difference.

 

[GerhardG]

Hi All

Thanks for the thread Mac, I believe this can save lots of people lots of money.

My 2c.......FWIW

Find an open space in your yard, bundle up a few pages of newspaper, loosely coil up your copper wire and place on top of the newspaper.
Light the sucker up.....
Wait till the newspaper's almost burnt out and....

....sorry Smoke, have to disagree ......

Hose the lot down so you don't burn your fingers.....
Done.

Just one thing, the thickest copper wire I can get is about 1mm, I assume you might need more heat with the thicker wire used (wish I had some!).

Most important thing: It's really that easy....

 

[lordy]

I learned here that annealed hot copper, pretty much regardless of shape (wire, tubing, etc.) can be quenched with cold water without altering it's pliability or softness. I have always been under the impression, like Smoke, that letting it cool slowly was the preferred method. I did some research online and found in numerous places that it may even be preferred to quench it instead.
As it pertains to me and my frequent and laborious (NOT) annealing sessions, I likely wont change because I am in no hurry to anneal and wire immediately, and my experience has been positive after letting it cool slowly. And I think it may just be a waste of water. But I appreciate the links Poink.

I believe that if you dont think you can still learn new things every day, you may as well just cash in your chips. And I'm not ready to leave this casino!

 

[Smoke]

I learned here that annealed hot copper, pretty much regardless of shape (wire, tubing, etc.) can be quenched with cold water without altering it's pliability or softness. I have always been under the impression, like Smoke, that letting it cool slowly was the preferred method. I did some research online and found in numerous places that it may even be preferred to quench it instead.
As it pertains to me and my frequent and laborious (NOT) annealing sessions, I likely wont change because I am in no hurry to anneal and wire immediately, and my experience has been positive after letting it cool slowly. And I think it may just be a waste of water. But I appreciate the links Poink.

I believe that if you dont think you can still learn new things every day, you may as well just cash in your chips. And I'm not ready to leave this casino!

Hmmm...no one gonna ask why copper is quenched?