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I have a fiber clamshell kiln that I am finding holds heat like it is hermetically sealed, but I am afraid to vent it because the shelf would be exposed to the outside air. Is there any way to safely vent this thing so my firings don't last an eon? Could I drill a hole in each side?

Thanks, Lisa

What is the size of the shelf, how thick is it, and what is it made of?

The shelf is 36"x48"x2" and is fiber board. Lisa

Lisa,

Bert added venting holes to the top of his bell kiln because it was so tight. I'll ask him to post details of his experience.

Tony

Some of my kilns have 1" fiber board liners, and my shelves are 20 x 20" mullite. I have repeatedly vented at much higher temps than I would ever recommend anyone else do:Sometimes as high as 900, often at 600, and regularly at 400. My boards and shelves have sustained no damage from this, so I don't think you have to worry. You could drill holes, but unless they're vertically stacked (one above the other) and big (1" or more) they won't do much. Cracking the lid and having different sized pieces of brick or whatever to hold it open is the more effective way to go.

Tony S-

I guess I wasn't very clear.......I am not so worried about the shelf incurring damage as I am the glass being exposed to cool air if I vent it, since the shelf is basically level with the opening when I lift the lid.

I think I am going to try to solve this dilemma by baffling around the shelf on the front and sides with 1" fiber board cut about 3" high. This will hopefully allow me to open the lid to vent without exposing the glass to direct shots of cooler air.

Lisa