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chimney, salt kiln

updated sat 31 aug 96

 

bill bosworth on thu 22 aug 96

Hi everyone,

I need to know what kind of bricks to use in the chimney of a salt kiln, and
how to calculate the hight of the chimney. Also how far away from the kiln
should it be? (how long should the flu channel be?) Thanks for you time!!

Happy potting,
Heather Dixon

WardBurner@aol.com on fri 23 aug 96

Heather,

The rule of thumb for chimney height is: 3 times the linear draw plus 1/3 the
interior height. So, if your kiln is 36 inches deep..., then you go through
9" of wall..., then another 9" to the back inside of the chimney, you have a
linear draw of 54". If your kiln is 48" tall, 1/3 of your height is; 16".
54 x 3 = 162 inches.....add the 16" and you get 178" or 14.8 ft.
You can share the back wall (make sure every few courses is "tied" into the
wall) with the chimney or have it set back a few bricks...Whatever works for
you. Since you're salting, I would go ahead and use hard brick.
My apologizes to the rest of the world that has enough sense to use the
metric system.....

Marc Ward
Ward Burner Systems
PO Box 333
Dandridge, TN 37725
USA
423.397.2914 voice
423.397.1253 fax
wardburner@aol.com

Heather wrote:
<<<<and
how to calculate the hight of the chimney. Also how far away from the kiln
should it be? (how long should the flu channel be?) Thanks for you
time!!>>>>>

Nan Rothwell on fri 23 aug 96


<<
I need to know what kind of bricks to use in the chimney of a salt kiln, and
how to calculate the hight of the chimney. Also how far away from the kiln
should it be? (how long should the flu channel be?) Thanks for you time!!
>>
I've always used any old hardbrick for my salt kiln chimneys. My current
kiln chimney is constructed of archbrick from a friend's old reduction kiln
-- it's a bit funky-looking, but still serves well after 80+ firings. I
figure that unless you're firing with wood (with its consequent long flame)
your chimney will never get terribly hot. You'll probalby want to use decent
quality (e.g., new and claen) brick to lay the first few courses -- just to
get the whole thing off to a level, even start. After that, almost any high
temperature hardbrick will do. I've always been careful to lay the walls and
arch of my kilns virtually dry -- but have needed a fair quantity of mortar
for the chimneys and they've survived. You might want to use a salt-friendly
castable formula for mortar -- let me know if you'd like a formula for one.


As for the length and size of the flue and chimney -- it depends on the size
of your firing chamber, fuel used, etc. Consult Olsen or Rhodes for the
standard formulae. It's probably best to err toward the slightly long on the
chimney, to be sure you get the main body of fumes pretty high and therefore
far from you. Are you planning to wear a decent respirator while firing?
YOU SHOULD!! I used to rely on old army-surplus gas masks, and always
ended up with powerful post-firing hangovers. Now I use a high quality mask
and feel much better the next day.

Good luck with it. And thanks again, Heather, for the lead on the new
version of B&W K-23's. I'm going to Richmond to pick some up for my kiln
door tomorrow!
Nan Rothwell

Randy Brodnax on sat 24 aug 96

Heather:

Get Nils Lou's The Art of Firing. Use Nils design for flue box and
metal stack (without double venturi) for chimney.

Over the last nine years I've constructed seven kilns. I'm currently
working on my eighth. It is the Peg Udall design out of Jack Troy's
Woodfire book. I believe it was designed by Ruggles and Rankin.

On the last two kilns, I used Nils flue box/stack design. The two
are identical in design, based on Brookfield kiln (sprung arch,
downdraft, hardbrick, approx. 30 cu. ft.) out of Studio Potter. One
is for soda the other for reduction firing. The fluebox/ stack works
great.

Rafael Molina
Instructor
Cedar Valley College
@
rcb3431@dcccd,edu