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best shelves for salt?

updated tue 31 dec 96


JOE BENNION on wed 4 dec 96

When the high alumina shelves from England came on the market claiming to
be great for salt I bought some and was very disappointed. I've had the same
experience with high alumina bricks used as posts in salt. After a number of
firings, let's say 15 or more, the bricks suddenly turn to mush and the whole
firing goes to hell in a few minuets. It is very disheartening to look in a
peep hole and see pots going down sideways. High alumina will resist salt
glaze buildup initially but absorbs the sodium and over time succumbs to the
fluxing action. For the money, and they are expensive, silicon carbide is the
best refractory for salt. Some people wash one side of the shelves with a kiln
wash like you are doing. It is a high maintenance route but works well. Others
don't wash the shelves at all. After each firing clean all surfaces well with
a rubbing brick. This is quick and easy. It also allows you to flip shelves.
The down side is that the whole shelf is exposed to the effects of sodium and
will wear away sooner. If possible I would order 1" or thicker. They last
longer and are great for building muscle bulk. Also if you can find or afford
them silicon carbide straights are the best for building your fire box and
bagwalls. Good luck and happy salting, vaporing(?).
Joe the Potter