OK - so not talking about my first try at copper clay because it was a disaster! :P But basically it was a looong fire time (it took me 1 1/2 hours to get to temp on my old kiln :( !!) But I am wondering if anyone has tried copper clay compared to bronze clay.  I ask because the advice I have read in here on bronze clay is so very good and am wondering if in practice it is the same as bronze clay firing.

I have an old german infinite control kiln which is, ironically, really difficult to control :)

Used my stainless tub, with pre-fired carbon (though I think the carbon may not have been the right one- activated but not sure if its coconut), and fired according to the time in the instructions which equalled 4 hours.  It was sintered to a crisp - it resembled carbon steel lol.

Anyway, any insight into whether I can follow bronze clay advice on copper clay firing would be welcomed :)

Should I try for less firing time or lower firing temp incase my kiln is out? does this sound like overfiring? Ok, so I am talking about my first try :P

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UPDATE Wednesday : tried a piece tonight with a lower fire temp and less time- worked pretty well though it warped a fair bit (no biggy - just flattened it in our press but worried about dimensional pieces in future :/ ). 

I suspect my kiln temp is out by a large amount!

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OK next update (thursday) I looked at my piece this morning and it seems to have tarnished a little - is this oxidisation caused from not firing enough? This is driving me a bit nuts! :) I can't seem to get it clean not even using the copper cleaning processes we use in enamelling...

thats a piccy of the test piece (front and back) with the tarnish/ox - any ideas?

I need help too!  After my first firing of copper clay w/ coconut charcoal (full ramp, 1650 hold for 3.5 hrs as per instructions) my stainless steel tub & lid are completely black & rough.  Is it supposed to do this?  I also had black charcoal dust all over the bottom of my kiln even though the lid was on the tub.  My tub is the smaller size, I put it on kiln risers, and I made sure it didn't touch any of the sides.  I purchased everything from a metal clay supplier.  None of my copper pieces (small charms) sintered well.  When I tried to clean them up, they look like copper on the outside, but then they break and the inside eats away like clay.  Every place where I used slip & fresh clay to attach copper wire bails it failed.  When they came out of the kiln that area of the charms looked black and all the bails fall right out.  The black areas just crumble.  Also the clay to clay connections are failing.  My kiln is a Paragon programable from Rio and has been very reliable on it's temperature control.  I fire silver clay all the time.

Is there anyway to salvage these pieces?  Should I fire on a different schedule?  Why is the freshly made slip failing?  It's all very frustrating.

While I cant help you with programming as I am having similar issues, I can tell you your SS tub is going to go black after the first fire - its perfectly normal and ok. The site and reputable supplier in Aus that I purchased mine from warns you to expect to loose that shiny nice SS surface after the first firing but its ok as its normal - no need to clean.

As for the copper clay - mine went native after the initial tarnish issue and I ended up with intense unfixable verdigre which I ended up experimenting with in an offsite kiln with enamel hoping I could sinter the copper further..didnt work and its not recommended because its quite dangerous. 

My first copper clay fire did what yours did and I addressed some of those issues with a lesser firing time which is why I suspect I had verdigre issues... sigh  I wish I could help bit there are just too few people with copper clay experience around :/