Copper inclusions: controlling oxidisation

Sandera · January 10, 2012, 08:42:28 AM

Whenever I use copper foil as an inclusion it invariably goes black! I would love to have even a small degree of control over the oxidisation process so that I can get blues/greens/reds. I currently take the pieces up to a full fuse. I'm going to do some experimentation myself but has anyone else had any success?

I've already done a bit of research about keeping the copper copper coloured but the sites are generally American and refer to American products. Does anyone know of a clear glass paint suitable for fusing?

Hope you can help!

Sandera

Zeldazog · January 10, 2012, 09:34:02 AM

What sort are you using, and what glass are you using it with?

If I use the Bullseye one http://www.warm-glass.co.uk/bullseye-copper-foil-p-363.html, I've always got the colours. I've usually got the reds out of copper wire too.

In the coasters, I couldn't control whether it was red or green, but none went black:

The only time I didn't get the colours was when I didn't use this type of foil - it was some other type of crafters foil.

I've usually used Bullseye glass, but I've used float glass both for myself and with students in classes and still got it.

Sandera · January 10, 2012, 10:43:38 AM

That's interesting, thanks Zeldazog. I've had the foil for a while and i can't remember where I got it from. I'll order some from Warm Glass (when they have it back in stock) and see how I get on. I'm going to try to lay clear frits on the copper to see what happens!

Warm Glass UK · January 10, 2012, 10:52:19 AM

Sorry it's out of stock - we keep increasing how much we order but it does seem very popular so we will air ship some in to beat our sea container. It should be here within about a week from today. Thanks.

ARBeads · January 10, 2012, 10:54:05 AM

Even Andy's sky scraper went red before collapsing under the sheer weight!

As I remember that was float.

Zeldazog · January 10, 2012, 11:09:29 AM

Ah yes, I remember the sky scraper!!

Zeldazog · January 10, 2012, 11:12:54 AM

I know this might be a silly question but you are sandwiching it between the layers, aren't you??

If its exposed it will go black...

Sandera · January 10, 2012, 05:27:42 PM

Quote from: Zeldazog on January 10, 2012, 11:12:54 AM
I know this might be a silly question but you are sandwiching it between the layers, aren't you??

If its exposed it will go black...

Yes - I'm doing that. Sometimes I sandwich it between 2 pieces of plain glass - other times between plain and coloured. Doesn't seem to make a difference - the result = black!

Glyn Burton · January 10, 2012, 05:45:34 PM

Hi, I find it difficult to get copper to do anything but go red so perhaps your copper foil is 'copper coloured' rather than the real thing. Aluminium is sometimes coated to give a copper effect and that will burn black. Do you know any electricians? if so ask for some off cuts of wire and strip off the insulation, this will give you lots of copper wire to play with.
Copper mesh/fabric can be interesting to use I think wire.co.uk (or something like that) sell it at about £25 sq M

Sandera · January 10, 2012, 06:27:36 PM

Quote from: Glyn Burton on January 10, 2012, 05:45:34 PM
Hi, I find it difficult to get copper to do anything but go red so perhaps your copper foil is 'copper coloured' rather than the real thing. Aluminium is sometimes coated to give a copper effect and that will burn black. Do you know any electricians? if so ask for some off cuts of wire and strip off the insulation, this will give you lots of copper wire to play with.
Copper mesh/fabric can be interesting to use I think wire.co.uk (or something like that) sell it at about £25 sq M

Could be. Although I'm pretty cautious about what I put in the kiln and I'm sure i would have bought copper that was advertised as copper. I wish I could remember where I got it from....Interestingly, now that you mention it, the copper wire I've fused has been fine. Mmmm - looking increasingly as though it could be a problem with the copper foil. I've got some on order though Brimmond Crafts so I'll keep my fingers crossed.

Zeldazog · January 10, 2012, 06:37:15 PM

I had some foil (bought from a craft supplies) that said it was "Copper Foil" but it turned black and was probably the stuff that Glyn describes.
It didn't say on the packet that it was anything other than copper , but I suppose unless its from a fusing suppliers, they might not expect you to be taking it up to high temperatures, and therefore don't see a need to explain.. or maybe, it *is* copper, but has a coating of some sort.

Sandera · January 17, 2012, 05:07:56 PM

You were right - it was the copper!! The new copper (from Brimmond crafts) comes out a lovely red. I've experimented with it: clear frit over the copper which gives nice textured coppery red; and red frit which darkens the copper quite considerably. I'll continue to experiment with different coloured frits and let you know how it turns out if that's useful.

Thanks for all your help - I don't think I would have thought the copper was the culprit. You've saved me loads of time.

Sandera · January 17, 2012, 05:11:07 PM

Quote from: Glyn Burton on January 10, 2012, 05:45:34 PM
Hi, I find it difficult to get copper to do anything but go red so perhaps your copper foil is 'copper coloured' rather than the real thing. Aluminium is sometimes coated to give a copper effect and that will burn black. Do you know any electricians? if so ask for some off cuts of wire and strip off the insulation, this will give you lots of copper wire to play with.
Copper mesh/fabric can be interesting to use I think wire.co.uk (or something like that) sell it at about £25 sq M

Oooh - must try that! thanks for the tip.