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firing closed/hollow forms?

updated thu 1 nov 07

 

Marianne Sheil on wed 31 oct 07


Assuming a well-dried pot, and a pre-heat in the bisque firing, are there any pitfalls to be aware of when firing a hollow shape? Is an airhole for escaping steam an absolute necessity? If so, how small a one can I get away with? In my case, I am firing electrically, bisque to ^04, then glaze to ^6 and the enclosed area is kind of a pod shape joined onto the flat top of a lid. thanks for any expertise you might share. marianne

Carlee Weston on wed 31 oct 07


Marianne,
You did not state if your pod was fixed to the lid pre firing or not. Iam going to assume that it is.

In my experience, yes, you do need a steam vent. It can be as small as a pin tool hole, I would suggest up through the lid into the pod and be sure that the hole does not get filled with glaze when you glaze.

Steam will form no matter how "dry" the piece and it will find a way to escape no matter what, so it is best for you to choose the route.

Carlee

-------------- Original message from Marianne Sheil : --------------


> Assuming a well-dried pot, and a pre-heat in the bisque firing, are there any
> pitfalls to be aware of when firing a hollow shape? Is an airhole for escaping
> steam an absolute necessity? If so, how small a one can I get away with? In my
> case, I am firing electrically, bisque to ^04, then glaze to ^6 and the enclosed
> area is kind of a pod shape joined onto the flat top of a lid. thanks for any
> expertise you might share. marianne
>
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