Peter Coates on sun 10 dec 06
I've wondered, with all this talk of soft brick soda kilns.... if a
person couldn't line a "small" kiln with hard bricks laid on their
side, their 2 1/2 " side ... so you would have 2 1/2 inches of hard
brick and then soft brick... I just don''t know the nature of soda
I have another question... do you all put mortar between the hard
bricks?... what keeps the soda from going between the bricks?...
Peter in Oklahellma City, Oklahoma
Vince Pitelka on mon 11 dec 06
> I've wondered, with all this talk of soft brick soda kilns.... if a
> person couldn't line a "small" kiln with hard bricks laid on their
> side, their 2 1/2 " side ... so you would have 2 1/2 inches of hard
> brick and then soft brick... I just don''t know the nature of soda
> I have another question... do you all put mortar between the hard
> bricks?... what keeps the soda from going between the bricks?...
The problem with lining the kiln with standard hardbrick laid on edge with a
thickness of 2.5" thick is the challenge of tying the two layers together.
If you don't they will separate and wreak havoc, especially in a salt or
soda kiln. When you lay the hardbrick with a 4.5" thickness, you can lay
"header" courses after every four or five stretcher courses, tying the two
layers of wall together. Of course the header courses have to be hardbrick.
If you had a ready supply of "soaps," you could do as you suggest. Soaps
are the 9" length of a normal hardbrick, but are only 2.5" wide by 2.25"
thick. So, you could lay a hardface layer of soaps 2.25" thick as you lay
the insulation brick outer layer, and after every four or five stretcher
courses you could lay a header course, which could be done with normal
hardbrick trimmed to 6.75" in length.
Generally hardbrick soaps cost at least as much as a standard "straight"
hardbrick, so I don't expect it would be worth the expense unless you found
a good deal on soaps.
With standard hardbrick, the hotface surface developes a glaze pretty
quickly. The soda penetrates the cracks initially, but seals the cracks
I hope that all makes sense.
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111