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I have pits in my kiln shelf after a pot melt. Is there anything to fill the pits? Sanding would take forever as they are quite deep.

I know that I have seen people talk of products specific to this, so maybe they will chime in. I myself have done some repairs using mold material such as Castalot. Mix it up, make sure the area that you are patching is good and wet so as to not suck the moisture out of the mold material, spread it across the pits and smooth with any tool with a flat edge. Let dry completely and lightly sand. Not permanent, but can get you through some firings.

dianebartlett wrote:I have pits in my kiln shelf after a pot melt. Is there anything to fill the pits? Sanding would take forever as they are quite deep.

It was previously suggested on this board to use thick kiln wash; worked for my pitted kiln shelf.

Thanks, I will try the Castalot. I did use a thick kiln wash and that does work for projects using thin fire paper. It does not work for my pot melts as you said it is only temporary.

You might try putting refractory cement into the holes, packing it in and firing according to the manufacturer's directions.

I don't think it's a permanent fix--if I'm not mistaken the cement and mullite have different expansion rates so eventually the cement will pop out--but it should last awhile. You can keep pushing the cement back in the holes and kilnwashing over it.

A faster fix is to simply sift dry kilnwash or plaster of paris over the kilnwashed board and then go over it with a flat spackling knife, smoothing and polishing the surface of the shelf until it's flat. That lasts one firing (or more, if you're very careful), and it's easy to renew.

Either way, I really avoid doing potmelts directly on a kilnshelf for obvious reasons. One option is to get a new kilnshelf and then use the pitted one for...potmelts. It would also come in handy when you want to do processes that require a second kilnshelf, such as compression firings.

Thanks, I researched the Castalot and it is quite expensive. I will look into the refractory cement. I may just bite the bullet and buy a new shelf. I can cut the old one up into damns. Yes, I did learn the hard way about pot melts. I use fiber paper now. Thanks for your help.

Diane,
One way you can avoid that problem and still use thinfire is to put 1 thickness of clear glass on the bottom of your pot melt containment. The melt drippings will fall on the soft clear glass and not disturb the thinfire. I have read this and done it a couple of times so I can't promise that there are no circumstances where this would fail. But, having the clear glass bed can't hurt.

Warren

there is a product called patch a tach used for repairing bisk ware. I have used it to repair molds and fill in scratches in my kiln shelf it can be found through most ceramic supply houses cheep and easy fix