A Bit of Kiln Housekeeping
I get that same feeling when it comes to housework inside. Not something that's to be enjoyed.....but it has to be done. No matter how long you put it off, it magically doesn't disappear.
That's how I feel when it comes to grinding off glaze dribbles and flaky kiln wash from the kiln shelves.
If you leave glaze dribbles on the shelves, your pots can get "hung up" on them and they're unable to expand and contract freely during the firings. I suspect it may be the culprit during the last couple or 3 firings where there have been cracks appearing on pots in the same area on the offending dirty shelves.
Hubby thankfully got the grinder out and cleaned most of the remaining flat shelves outside....that's the worst job, quite dusty work.
There were 4 shelves that had a significant bow, so they will have to be replaced. Two of them were thinner and weren't up to the high firing temperatures that I get up to. The replacements will have to be a bit thicker.
I use bought kiln wash. In the past I've mucked around with homemade recipes but have had issues with it flaking off after only one or two firings, so just not worth the effort.
The kiln shelf wash is thin once you mix it with water. You have to use at least 2 or 3 coats with it drying in between.
Why do you need to coat the shelves with kiln wash? It helps the pieces being fired to move on it as they expand and contract during the firing. They would tend to get "stuck" and crack or tear apart without it. A bit like having a fine layer of ball bearings for the pieces to slide around on.
The jobs all done, and they're about to get dried out properly in the kiln before the next firing....which will be very shortly.