Saturday 2 January 2010

Art Clay Copper - Firing & Polishing

Copper pieces all laid out ready for firing. The kiln needs to get to 970 degrees C. I used my enamelling fork to lift the pieces into the hot kiln. The temperature is held for 30 mins & you take them out HOT!
The pieces are dropped hot from the kiln into cold water. This was difficult as many of them were trying to stick to the fibre shelf. (Prying red hot bits of copper off a fibre shelf is not fun!)
Once pickled (which has left my pickle pot in a right mess) the pieces were tumbled in shot for 45mins. Very easy to see the copper in the steel shot (a pleasant change from trying to spot bits of silver).Dried & separated from the shot you can see a few bits of scale which I plan to take off with a burr. The scale seems to stick to straight pieces more than any other shape. The strips were very bendy, dead soft copper (the ones I rolled 4 cards and 6 cards thick).
I plan to hammer these to work harden them.
Some of the Finished pieces - Five Art Clay Rings (hmmm maybe I should make some calling birds next!). I've done a little smashing on my ring mandrel but plan to do some more ~ these definitely have possibilities...maybe the centre of some spinner rings?
The sizes they ended up were:
9 ended up an 8 (size P)
10- ended up a little over 9 (R1/4)
10 ended up 8 3/4 (almost R)
11 ended up 9 3/4 (approx S 1/2)
12 ended up 10 1/2 (little over U)
The 12 was done with the Red, 6 card, Rio slats and I prefer the result so would suggest using 6 card minimum.
Hope that helps & the end result is Art Clay Copper is well worth giving a try!
Nic xx

38 comments:

  1. I love how bright they are. I might have to get a tumbler, next on the list of many things to buy :S x

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  2. Definately - You need a tumbler it makes life soooomuch easier :)

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  3. I love those! Hey Nic, I seen a kiln that works via the microwave. Do you know anything about those? It was really cheap and I was considering it. Happy New Year and thanks for all the knowledge! :)

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  4. Thanks Stacey :)
    While they DO work I wouldn't buy a Microwave Kiln as they're not accurate enough.

    To quote Tim McCreight (who wrote what is pretty much the metalsmiths bible)
    "One immediate problem is it is very difficult to know how long to run it. If you consider that most microwave popcorn packages say something like "Heat for one to six minutes, depending on your microwave," you get an
    idea of how different the units can be. If you are making a dozen identical pieces, and don't mind melting or under firing the first ten, you can determine the proper time for that unique shape and get those last two right.
    Not an ideal arrangement."

    I'd suggest a good torch would be more reliable. PLUS once those hot metal gasses
    have vented through the top into the microwave itself, you shouldn't then use if for food...

    The pros:
    1) Cheap initial outlay

    The Cons:
    1) You contaminate your microwave
    2) It's not suitable for hollow forms
    3) No temperature control or way of viewing
    4) Can melt you pieces as each microwave is different

    All in all I'd save up and buy something like the Ultralite Kiln or save even more and buy a small Paragon, Prometheus or Evenheat...

    In the mean time good torch control would probably do for a lot of pieces
    Nic x

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  5. Hi Nicola,
    Thanks so much for sharing your experience with copper clay. Your pieces turned out beautifully. I had no idea you could fire copper clay with a torch. I agree about the microwave, the contamination factor is what scares me the most. Debora

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  6. Great I found your blog! Fab copper pieces love them!

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  7. Hi. Nic. Thanks for your blog, very informative, I have just bought copper clay and found your information gave me more confidence to have a go. Just one question I might have been imagining it but I thought that I had read somewhere that it is better stored in a fridge, or am I mixing it up with an other clay?
    Ann

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  8. Hi Ann
    Glad it helped :)
    The container fired clay seems to work better out of the fridge but the Art Clay Copper says to store at room temperature. (It was fine at room temp)
    nicx x

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  9. Hi. Nic.
    Thankyou, I have another question.
    I have started to make things out of this clay and I wanted to add cz's but after reading your blog about quenching as soon as you brought them out of the kiln, I was wondering if items could be left to cool down slowly?
    Ann

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  10. Yes they can be left to cool down slowly,
    cover them with a fibre balnket while they do, as the scale can ping off.
    Oncwe cool you'll have to remove the firescale manually, pickle and clean, pickle and clean (it will take a bit of work)
    nic xx

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  11. Thanks again, sounds like hard work but I'm sure it will be worth the effort.
    Ann x

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  12. Hello,

    I really enjoyed your blog..it's very helpfull. I will be trying Art Clay Copper soon and i was wondering if i have to have a separate barrel and stainless steel shots if i want to tumble the copper.

    Thanks
    Martine

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  13. Glad it's useful to you :)
    Nope you don't need a different barrel & shot,
    I just rinse the shot off and add fresh fluid before I next polish silver.
    nic x

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  14. That's good news. :) Thank you so much.

    Martine

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  15. Hi. Nic.
    Just taken delivery of my new SC2 Paragon kiln, it has a viewing window and according to the instruction book it can't go higher than 1700F/926C or it will damage the glass, and as I want to fire copper clay in this kiln
    have I got a problem or can I fire at a lower temp. for a longer time?

    p.s.
    I noticed that you have a window in the door of the kiln that you used for the copper clay.

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  16. Lol - Oh bugger you caught me out (I forgot to read the manual). However it's easily solved just plug the hole up with some kiln block cut to size.
    I do that on my bronze firings :)

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  17. 'scuse my ignorance, what is kiln block?
    Thanks
    Ann

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  18. One of those white fire proof brick things :)
    It's shown here on the Paragon site
    http://www.paragonweb.com/Kiln_Pointer.cfm?PID=327
    Nic x

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  19. Thanks Nic. They supplied some sort of fibre to plug the hole, but I misunderstood the instructions.
    I'm of to switch it on now, wish me luck, I don't know what I would do without this blog.
    Ann xx

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  20. Hi. Nic.
    O.M.G. that was a scary experience, I've got the copper in a pickle solution, how long do I have leave them in there?
    Sorry to pester.
    Ann xx

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  21. Congratulations - sounds like you've fired your first copper clay! :)
    I left mine in for a few hours and brushed them every now and again to get the scale off.
    The rest came off with some wire brushing
    nic xx

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  22. Hi. Nic.
    Thanks very much for all the help, the copper is almost ready for tumbling now.
    Ann xx

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  23. Hi Nic -

    Just a thought, but a piece of Thinfire paper (or even kiln wash) would make removing your hot copper from the fibre much, much easier.

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  24. Thanks Peter
    I'll give that a go next. I tried steel rack last time and it even stuck to that!
    Will let you know if it works :)
    nic xx

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  25. I'll be surprised if it doesn't... Mind you, kiln wash on a steel sheet is cheaper.

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  26. Wow Nicola , those copper rings are lovely

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  27. Hi. Nic. Thanks for the answer to the pickle question, the first lot of copper cleaned up quite quick, I did them in a jar in a pan of water on the hob, then I thought I would treat myself to a slowcooker from Argos, I have had the second lot of copper in there since yesterday am. they are still not clean, I keep taking them out and brushing it's not working, any ideas.
    Ann x

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  28. Try mixing up fresh pickle solution if they are still coated then maybe it's howfast they got dropped into the water (freshfromthe kiln)-Some people have pulled the pieces out one by one & noticed the last piece often has more difficult to remove fire scale on than the first.
    With mine I tip them all in together - which is quite nerve wracking (visions of hot metal skittering across the floor).
    Seems to work better that way though :)
    Nic x

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  29. Nic! Thanks for the insight - I'm looking forward to my first copper firing tomorrow!

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  30. You're welcome - hope the copper firing goes well :)

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  31. so glad you were able to share all this and run round hopping into jeans and scoffing buttered toast! I realize this is from January :) really what a happy accident I found this. Not many share what they've done with art clay copper and I wanted to make a ring. Did you hammer the strips? can those be pressed round a ring mandrel?

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  32. Lol - yep that's my morning ritual for you!
    I made the rings as rings the hammering was just to true them up into round after firing.
    Having said that they seemed to keep their shape pretty well whilst drying and firing :)
    The strips are overlay decoration strips for soldering onto sterling or including in silver clay pieces....
    Nic xx

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  33. thanks so much for the feedback!

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  34. I love how these turned out!! It's interesting to me that the straight pieces were dead soft - but I'm betting you did something wonderful with them. I need to go read up and see if you've posted about them...

    Thank you for the evaluation. I've wanted to play with it but haven't. (I should mention I'm using a torch since I haven't purchased a kiln.) I love reading what you have to say about it - and your pictures are fantastic. Thanks!!

    xx,
    Katherine

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  35. I am so glad I found your blog. I just started working with ArtClay Silver in January and got my first package of copper last night. I was so freaked out and afraid to try to do anything with it. Thank you! LOL I'll be torch firing - I'll be posting on my blog once that starts going anywhere. ROFLOL

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  36. Wonderful work!
    I am having a terrible time with my Art Clay copper clay. When I take it from the pack, it is hard as a rock. How do you soften it enough to work with?? I tried adding a few drops of water, but that didn't work. What am I doing wrong? Is it possible that it's just old? It was an unopened pack. I have worked for a long time with PMC silver and this is my first attempt with copper.

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  37. Hi! I just found this page via Google and I was wondering something.

    I'm planning on setting up to do copper PMC and enamel. I was wondering if after the sintering and pickling process is it safe to re-fire these pieces to do the enamel? For technical reasons the enamel firing would never be above 1650F.

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  38. I just fired at 1778 for 30 mins and quenched, but my pieces are raspberry colored rather than copper colored...?

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