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nammie
03-08-2012, 02:09 PM
Hi,

I'm new to this forum and fairly new to all things jewellery but I'm trying all sorts of new things. One thing I have experimented with is metal clay but I'm struggling with the copper version, can anyone help please?

Silver clay I can fire fine on the gas hob but I've bought a torch to help me with the Art clay Copper. Still, everything seems underfired and crumbly! Could I be a) not firing correctly? I'm heating to cherry red (and I've tried brighter) for at least 10 minutes (and I've tried samples for longer)
b) being a bit of a dunce with the torch?! I have a little Silverline one, it takes butane fuel and claims to reach 1300C. That said I don't seem to be able to ball up sterling or copper wire in it. Is there a trick to filling it correctly perhaps? Could that be why I'm not getting the correct temperature? (I'm struggling to light the flame sometimes and it doesn't seem to burn for very long)

Any thoughts would be very gratefully received as I'm thinking of abandoning the copper as a bad job but was hoping I use the torch for soldering etc

Thank you!
Nammie

mizgeorge
03-08-2012, 03:46 PM
I suspect you need a hotter, better torch.

For firing metal clays, the PT500 does an excellent job - nice big bushy flame, and big reservoir for longer firings.

http://cpc.farnell.com/1/1/70444-gas-torch-gas-heavy-duty-pt-500-pt-500-iroda.html

It's useful for annealing as well.

Melanie De Castro Pugh
03-08-2012, 03:59 PM
Hi Nammie, I use copper clay quite a lot using a butane/propane Go torch that was about twenty quid in B&Q, I think they burn hotter than the butane refillable ones. For firing I usually give copper fifteen minutes with the clay at a really hot orange glow, so I can see green flashes across the piece. But that's just me, I like to keep it just shy of melting! You need to make sure your pieces aren't too thick (they say the max size is a fifty pence piece), or they need kiln firing. My torch will melt copper, so if you're having problems balling sterling, that would suggest that yours isn't even getting to 800C.

My final test after firing is to chuck the cooled piece on my kitchen floor. If it sounds like metal, it has fired properly. If it crumbles or breaks.... well I'm sure you get the idea! Or you could just tap it and fire for a bit longer until it sounds metallic :-)

Hope this helps x


Melanie

http://www.spinysharklythings.com

Kwant
03-08-2012, 04:06 PM
Some time back it was mentioned that overlong use of the little refillable torches such as the one you have Nammie, can result in them becoming dangerously hot. Something to bear in mind if you are firing at full blast for ten minutes or more.

nammie
04-08-2012, 05:56 PM
Thank you all for your suggestions.

I perservered with the torch and found a set of instructions on the internet - I was being a dunce! However, I have to say the instructions provided with the torch were lacking some important elements like how to fill it correctly, light it and adjust the flame! (If you have a Silverline torch it might be worth a quick google to Silverline Tools)

Having followed the new instructions I got a much better result, I have managed to ball copper wire and, errrm, melt a bit of copper clay. I did also throw it on the kitchen floor as suggested but it wasn't deliberate (any tips on finding the little fiddly pieces!?).

Kwant, you're quite right, the torch does get uncomfortably hot but I think it will cope with the little bits I'm doing just now. Hopefully I have a place on a silversmithing course in September so I will wait to see if I fancy anything bigger after that..

Nammie

nammie
10-08-2012, 11:38 AM
Progress update: having found some genuine instructions for my torch online I've used it a couple of times now.I was a little annoyed when the label indicating on/off melted and fell off but now the whole thing is melting!
I've been on the phone to the company I bought it from but am awaiting a call back. Not sure whether to be cross, embarrassed or just plain scared....