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Author Topic: Hollow metal rods as an armature  (Read 3023 times)

Rittmeister

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Hollow metal rods as an armature
« on: August 04, 2011, 09:40:57 PM »
Hi, I figure this is the right subforum for this question.

I need to build an armature for a model. I bought a long, hollow metal rod because I thought that might be easier to cut. Alas I didnt think of it being problematic, but I remember from school crafting days with clay that in order to fire the clay properly, there mustn't be any enclosed hollows because the air in it would expand and eventually crack open the model.

Do you think that would be the case using this for the armature?

rubyrube

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Re: Hollow metal rods as an armature
« Reply #1 on: August 04, 2011, 10:37:11 PM »
Sorry, not had any experience of using hollow metal rods, I've only used foil and wire. You could try a test piece.

Carol
Carol

ejralph

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Re: Hollow metal rods as an armature
« Reply #2 on: August 04, 2011, 10:57:55 PM »
I think it would depend how thick the surrounding clay is and just how much air in the hollow rods?

It could expand enough to crack the clay - but not a spectacular in-kiln explosion in the same way that ceramic clay would.

Maybe you could have the hollow rods open at the base somehow so there is an exit hole for the air?

Failing that, build the armature out of a wire skeleton, filled with aluminium kitchen foil.

Emma
Emma from Sunny Sussex, UK
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Rittmeister

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Re: Hollow metal rods as an armature
« Reply #3 on: October 03, 2011, 07:36:37 PM »
Well, I had a try and found no problems, no cracks or anything. Could also be because the temperature used with polyclay is a lot lower than baking actual clay.

ejralph

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Re: Hollow metal rods as an armature
« Reply #4 on: October 03, 2011, 10:57:35 PM »
Oh thats good to hear - thanks for letting us know.

I think you are right, the heat isn't that much for polyclay. Also, when its warm, its quite flexible too so probably can accomodate a little air expanding and contracting without too many issues.

Emma
Emma from Sunny Sussex, UK
www.ejrbeads.co.uk Projects, articles, bead galleries & more
www.ejrbeads.co.uk/shop Art beads, clay & jewellery supplies