Ceramics Question

[Guest]

I'm writing a story that includes firing ceramics in a kiln. Can anyone tell me how many times a piece needs to be fired to be finished? And how long it takes to fire it?

 

[Weird Harold]

I'm writing a story that includes firing ceramics in a kiln. Can anyone tell me how many times a piece needs to be fired to be finished? And how long it takes to fire it?

From Porcelain Doll Making in Detail:

"...Many suggest the Kiln lid be propped open 3 or 4 inches for the first two hours. Gases and moisture need to escape. The longest time is with the kiln on highest heat, because the soaking time is when the porcelain gets the translucent quality you would like. When the Kiln is on Medium you could leave it overnight, or eight to ten hours.

"Once the kiln is turned to high, usually it will take another two hours to trip the cone-setter, but it it will take all day (or night) to cool off. Lay your hand on the lid. IF it is warm, don't open the kiln.
"... Just a little peeking could cause a draft and crack what is in the kiln."

While my mother's book (which is why I just happen to have the info handy) deals with making porcelain dolls, she also did a lot of ceramic painting on lozenges made from the same slip. They were often fired with the doll parts both before and after painting.

The firing described above is from the section on firing greenware to the bisque state. The same timing would be repeated for firing the glaze and or paint into finished doll parts.

E-Mail me if you need any more info on porcelain doll making, or ceramic painting. If the book doesn't have it, I can always call my mother and ask. (assuming she's not off galavanting around the west with her boyfriend again. <G>)

 

[Guest]

Wow that was fast!

From Porcelain Doll Making in Detail:

"...Many suggest the Kiln lid be propped open 3 or 4 inches for the first two hours. Gases and moisture need to escape. The longest time is with the kiln on highest heat, because the soaking time is when the porcelain gets the translucent quality you would like. When the Kiln is on Medium you could leave it overnight, or eight to ten hours.

"Once the kiln is turned to high, usually it will take another two hours to trip the cone-setter, but it it will take all day (or night) to cool off. Lay your hand on the lid. IF it is warm, don't open the kiln.
"... Just a little peeking could cause a draft and crack what is in the kiln."

Thanks WH you are a Guru! Now I have to change my story. I had the whole sculpture fired in one evening. Oh well, its a small part. I think they should have a stump WH contest to see what you can't answer.

 

[Weird Harold]

Re: Wow that was fast!

Thanks WH you are a Guru! Now I have to change my story. I had the whole sculpture fired in one evening. Oh well, its a small part. I think they should have a stump WH contest to see what you can't answer.

If it is an unpainted sculpture, it can be done in one firing. The second firing is for the glaze and paint.

I have all sorts of answers in my head. It's nice when one of them matches up with a question.