Parrot

[dolly]

I'm sculpting a parrot with earthenware clay, I've hollowed it out and fixed the high temp wire through it's body and have 2 wire running down the parrots legs for he's perch. should i make some holes in him for the air to flow through and will he be ok to fire , grown quite attached to him lol anyone got any suggestions please ...

[Babs]

The deal is, if he is absolutely dry there is no prob. with air in his interior!

Dampness is the prob with firing clay.

[dolly]

thanks yes I will make sure he's bone dry b4 I fire him , I was just worried about the wire, but needed something to connect him to a perch when he's fired cos he's going to be pretty heavy....

[Benzine]

An air vent will help it dry a bit faster though.

[neilestrick]

I would not trust wire to hold a sculpture in place during a firing. It will soften as it heats. You would be better off firing it on the shelf, laying on its side, held up with stilts.

[Benzine]

Good point Neil. And the good thing about Earthenware, is the metal pointed stilts can be used for the bisque and glaze firings.

[neilestrick]

Let it dry 3 times as long as you think it needs. With a closed form, it will appear dry on the outside but still be quite wet inside. This is why closed forms often blow up, not because of the trapped air. It's a good idea to do a long preheat, too. We regularly fire closed pieces in my studio without problem, but we let them dry forever and do a good preheat.

[Bob Coyle]

I would definitely put a small non obtrusive hole somewhere into the hollow portion. My paranoia about trapped moisture may be a little greater than the rest of the opinions here but why take the chance? I've blown pieces I would swear were as dry as a bone.

[neilestrick]

I would definitely put a small non obtrusive hole somewhere into the hollow portion. My paranoia about trapped moisture may be a little greater than the rest of the opinions here but why take the chance? I've blown pieces I would swear were as dry as a bone.

 

No matter what, it was moisture that blew it up. Could be that the firing was too fast. Since the heat only penetrates from the outside on a closed form, they take a little longer to evaporate off the last remaining bit of moisture.

[Bob Coyle]

Yeah Neil, water will do it every time. I wonder though, what happens to the water released inside a closed form during the time chemically bound water is being gassed out? There must be some gassing out inside as well as outside??

[neilestrick]

Yeah Neil, water will do it every time. I wonder though, what happens to the water released inside a closed form during the time chemically bound water is being gassed out? There must be some gassing out inside as well as outside??

 

Any pressure building up inside the open space in a closed form is not enough to do any damage. The walls of the pot are thick/strong enough to contain it. But when the steam forms inside the walls of the pot you don't have that thickness/strength since the water is between the clay particles. Also, by the time chemical water starts to burn out, the atmospheric water is already gone, as well as a lot of the organic/vegetative material, so you have a more porous body at that point which can handle the evaporation more easily.

[Babs]

So the wires you are speaking of are going to be fired in situ and are his legs when the piece is finished?

There was a post here about that  better do a search or,

Tyler has written about this in a couple of posts.

[dolly]

I bought the wire from my pottery supplier can withstand the heat. yes I think i will drill a hole in him just to cover myself. and wait so i'm sure he's dry. then say a little prayer whilst he's being cremated or created thanks for all your replies ...