Torch-firing Hadar’s Clay™ – Quick-fire Copper

Torch-firing quick-fire copper is much like torch-firing low-shrinkage silver clay: the piece will not be as strong as it can be when kiln-fired, but for pieces that don’t undergo wear and tear, or components that are not a structural part of a piece, this may not be all that important.

It takes a little longer, about 6 minutes. I suggest turning on the radio and listening to two songs in a row (or just Hey, Jude) while you are torching. Here is a video clip demonstrating firing a copper piece, 6 cards thick, and an overlay of copper clay fired over steel clay:

Jenny James sent me an email, saying that she wasn’t able to sinter quick-fire copper with a torch, even after 20 minutes. She ended up firing it on the screen on her stove top for 30-40 minutes and succeeded.

If you try that, you can do it outside, using a burner that is used for camping. Place a screen or copper sheet over the burner and place the pieces in a circle, where the flame is.

I answered Jenny that what I think happened, is that her torch did not supply enough flame. Either the flame wasn’t big or hot enough, or the piece was too big for torch-firing. The flame has two roles in base-metal clay firing:

1. To supply heat;
2. To consume the oxygen around the piece in order to prevent oxidation. In fact, that’s what the carbon does by burning. Here is a photo of the carbon burning right after the kiln finished its cycle.

Obviously there was much more flame on the stove to protect the piece from oxygen.

So Jenny went on to her second experiment. Here is what she wrote:

“More heat and less oxygen when torch firing, I tried something new. I laid the piece ON TOP of a little dish of carbon. I then fired for 8 minutes with my small butane torch. It heated up WAY faster to a much brighter glow, and the piece was entirely engulfed in flame. It sintered BEAUTIFULLY in 8 minutes and was super strong! I will keep testing it for shorter periods of time tonight and see just how quick it can really be fired.” Later she wrote: “In 4 minutes the piece sintered perfectly and was super hard – unable to break it with pliers. All of the tests were done with 8 mm thick and 2 cm x 2 cm. By firing it on top of carbon it fires as easily as torch firing silver.”

I’d like to thank Jenny for her input. I would also like to thank Ron Taylor, who sent me a photo of a piece that he created at my workshop in San Diego. Ron came to class with a rendering of a piece that he wanted to make with a combination of copper and silver, and the piece came out exactly as he planned it, including its size!

Ron


20 Responses to “Torch-firing Hadar’s Clay™ – Quick-fire Copper”

  • Finola Prescott Says:

    Thank you for these lovely and clear instructions – for those of us in countries where classes and experts are hard to be found, having videos and i like this are invaluable. Much appreciated

  • Finola Prescott Says:

    sorry, typo – that’s not “i” it’s “instructions” – while “i” certainly has its uses, I find instructions much more helpful :)

  • Hadar Jacobson Says:

    Finola,

    Where do you live?

    Hadar

  • Christine Damm Says:

    I haven’t visited in a while due to reading your books that I just purchased– how could I have missed this exciting new development?? I have to digest the info but this method of torch firing will help me to the small pieces I’m wanting to do without purchasing a kiln right away so I can see if this metal is something I want to pursue. Thanks for all the technical help, Hadar! It really makes a difference.

  • Darla Says:

    What a terrific video,livley and informative I orderd the copper and bronze quick clay a short while ago. I’ll be watching for the postman torch at the ready!

  • gordon Says:

    Good idea about firing on the carbon.

  • Dawn Says:

    Can this technique be used with the bronze as well?

  • Hadar Jacobson Says:

    Dawn,

    It applies to copper, bronze, White Bronze, and steel.

  • Hadar Jacobson Says:

    Dawn,

    Correction, strike that. Only tiny pieces of copper clay can be torch fires. It does not work with bronze.

  • Linda Says:

    Hadar, I thought you retracted using a torch on any of your clays. Do you still recommend torching copper with carbon?
    thanks,
    Linda

  • Hadar Jacobson Says:

    I do not. In a video that was made a long time ago I showed that it is possible with very small pieces. I am going to try to remove the clip from YouTube since it causes a lot of confusion.

  • Disie Says:

    Quick question for you….

    When you do it on a camping stove top if the pieces are 3mm how long would you need to fire it for??

    Many Thanks

  • Hadar Jacobson Says:

    Disie, About 6 minutes. However, I am not a big fan anymore of torch firing.

  • A. Walters Says:

    Dear Hadar,
    Every time I try to torch fire copper clay, it simply turns black and disintegrates.
    What am I doing wrong? (I do not have a kiln.)
    Also, is it possible to use a thin layer copper clay to “keum-boo” fine silver clay pieces?
    Thank you so much.

  • Hadar Jacobson Says:

    I really don’t recommend firing copper with a torch. What you describe sounds like bad oxidation caused by exposure to heat and oxygen. Eventually you are going to need a kiln. About “keum-booing” copper on silver – it may be possible, but not with the same technique as gold.

  • Alcina Nolley Says:

    Hadar, I see Finola didn’t answer about where she lives. We both live in the Caribbean, St. Lucia to be exact. We both avidly read your blog and the metal clay list. We value the generous metal clay community and you very much. Season’s Greetings….

  • Michelle Says:

    Why the complete turnaround on torch firing copper. Why are you not recommending that?
    Is it the fumes?

  • Hadar Jacobson Says:

    Michelle, It’s not the fumes. Torch firing produces extremely week pieces and exposes them to oxidation.

  • Tammy Says:

    Does this technique work with steel also?

  • Hadar Jacobson Says:

    Tammy, What steel do you mean? I used low shrinkage steel XT.

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