I swung by and fixed 3 kiln shelves - both bottom ones plus the one that had the glaze run. I was able to chip off all the drips and runs without resorting to my dremel. I reapplied kiln wash and placed them back by the kilns to dry. I wasn’t able to stick around until they fully dried or help them along with a heat gun. They should be fully dry and usable before too long.
I did grab a fourth shelf to bring home to repair. It had several glaze run rings on it and kiln wash had been applied over the glaze spots. While the effort to fix the shelf is super appreciated, this isn’t the proper way to get the shelf back to a usable state.
To repair a shelf, all glaze needs to be removed. The more stubborn runs need grinding with a diamond bit. Kiln wash is applied once the shelf is glaze free. Leaving the glaze on and just covering it will result in 2 issues - 1. the glaze can come up out of the kiln wash as it’s fired and 2. the glaze will penetrate deeper into the shelf with each firing and eventually bond permanently with the shelf. This weakens the shelf and can result in cracking and breakage at some point. Also, the more it’s fired, the harder the glaze gets. It can get hard enough that attempting to grind the glaze off with a diamond coated bit becomes nearly impossible.
I was able to chip off some of the glaze on the fourth shelf, but there’s parts that need to be ground. We do have several shelves where there are permanent glaze rings permeating deep into the shelf. When we did the initial shelf cleaning and repair we declared several shelves as unfixable because of this. These are kept in a particular spot and the firing team knows not to use them.
A few of our shelves we ground down as deep as we were willing to risk, then did heavy layering of kiln wash to cover what we could in an effort to salvage a usable shelf. We opted to do this so we could have enough shelves to fire with until we get replacements. We watch those spots and apply kiln wash as needed to keep pieces safe. This shelf may be one of non-useable ones or had preexisting permanent glaze rings. I’ll know more once I start grinding in the next few days. If the glaze runs are new, I should be able to get them taken care of. If they’re older runs, I’ll do what I can to get it back to a usable state or declare it dead and place it with the others.
The last thing I grabbed was a small post with quite a bit of glaze run on it. I was able to chip off about 1/3 of the run and should be able to grind the rest off. I’ll get the post and shelf back up to the space in a few days.
