High Temp Wire Question

[yappystudent]

In a nutshell: Can you use this stuff inside of clay as an armature to reinforce thin bits of ceramic work? -Both straight clay and paperclay. Thanks in advance if anyone knows.

 

Non-essential reading below:

 

Example: some frillier than usual jewelry focals with narrow 'waists' that won't be possible unless they have some kind of rebar inside. My only other option is to make two separate pieces and attach them after firing by leaving holes in which to insert stiff wire perhaps, anyway that wouldn't end up being the same finished look I want. 

  I have some of this wire in two different gauges, and it isn't cheap, so it would be strictly for small work and I'm not married to the idea 100% due to cost. Also I pay to have my work fired and try to keep things as kosher as possible to avoid ruffling their feathers, heaven forfend I mess up their kilns, they hate me already for bringing them tons of tiny objects. I've asked them directly "is this possible" and got an all-too familiar "do what now?" -Still have no idea. 

 

 

[High Bridge Pottery]

I think the issue with adding an armature inside the clay is as it drys the clay shrinks but the wire does not leading to issues. Could be possible but could also fail a lot.

[Marcia Selsor]

test it. I think there is more potential with paper clay which would have more "give" around a solid object. Use the smallest gauge you can.

Marcia

[Chilly]

I used wire to attach the nose of a snowman.  The nose shrunk away from the snowman, but not around the wire.  The nose is intact, and, many years later, still standing in the garden.

 

Not sure what the wire was tho'.

 

Test, Test, Test.  (Which I didn't, of course.)

[oldlady]

yappy, are you talking about nichrome wire?  at what temperature?

 

to make the kiln owner happy, may i suggest you buy a shelf of your own and load it before handing it in for firing?  who could object to that?

[neilestrick]

You can use the wire inside small pieces, like jewelry. But in anything larger it will bend under the weight of the piece and the heat of the kiln.

[yappystudent]

Thanks for all the info and suggestions. I will go ahead and devise some tests.

 

Oldlady: Yes I believe it's nichrome wire. It's stuff I've used before to hang beads on during ^6 glaze firings, using some self-built bead trees. I couldn't tell you what the gauge is.

[Tim T]

I've played with using plain steel in large pieces to prevent them collapsing in the kiln - about 30" long and from memory 1/4" / 5mm diameter. These are fine for a cone 6 firing if there is no soak, though you'll need something with a higher melting point for cone 10.

Shrinkage and expansion are issues - the clay will shrink on drying, and then again on firing, which may be towards or away from your metal armature. Also, of course, the metal will expand when heated and contract again afterwards. I forgot this so had holes in the fired clay at the top, with a few mm of metal sticking out, which had to be cut off and plugged with epoxy. If doing this again I would prbably make the end of the rod cardboard or tape or something so it created space for clay shrinkage/metal expansion, though you may not need this at your scale of work.