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your soda kiln

updated tue 14 mar 00


Jeff Brett on mon 13 mar 00

Hi Pat,

Sorry I didn't get back to you right away. This is my email at work and I
do my best to put it aside on weekends.

Our cast kiln is a modification of the cast kiln in Ruth Tudball's book. We
made ours a bit taller and longer. It is 54" wide (outside), 48" long
(outside) and 39" inside height (floor to top of arch). The cast walls are
4 1/2" thick. You should modify the width, height and length to suit your
needs. Ours is a good size for student firings, small enough that they can
fire it often without having to produce alot of work. We oversized our
chimney a bit much so it drafts too well. When we relocate it next year
we'll redo the chimney.

It was a great learning experience for us to build one. One graduate have
since made her own kiln and learned much from our mistakes. A second
student plans to make one soon and I am sure will be able to draw on our

The casting process is the most time consuming and difficult part. It pays
to have many helpers to complete the process as quickly as possible.
Getting a smooth cast on the inside of the kiln is crucial. We didn't with
ours and even though the kiln was sprayed with ITC100 we still have decay
in the rough areas. We fire with tiger torches right now but plan to refit
with venturi burners soon. The kiln fires easily to cone 10 with four small
torches, two in front and two in the back.

Check the Clayart archives for articles on Cast kilns. There are a huge
number of posts. At one time there was an excellent web site at which showed construction of a cast
kiln. Tried it today but it wasn't available. Might just be a temporary
thing. I don't have a web site for our clay department yet but hope to
soon. Will let you know when I do. If I can borrow a digital camera this
week i'll snap a few photos and send them your way.

Email if you need more info.

Our recipe for the castable is by volume
2 parts fireclay we used lincoln
2 parts sawdust mix of coarse chips and fine sawdust
2 parts grog we ground up soft insulating brick and screened it thru a
1/4" screen
1 part cement fondue

I've included our Cast Salt Kiln costs for you (in Canadian dollars)

Kiln Base 24 Masonry Block $46.80
Base for castable 60 Light duty Hard Brick $105.00

Castable Mix for base, kiln arch, back wall and front door blocks

Lincoln Fireclay 15 50 lb bags $146.25
Coarse Grog 15 50 lb bags $324.45
Cement Fondue 5 100 lb bags $251.40
Sawdust/wood chips same volume as fireclay free

Chimney 180 Light duty Hard Brick $315.00
Flue 36 Moflint high duty brick $93.60
Bagwalls & posts 26 Moflint high duty brick $67.60
ITC 100 Kiln coating 1 gallon $255.00

Total $1605.10

At 8:03 AM -0800 3/9/2000, Pat Lindemann wrote:
>Jeff -
>Noticed your post in Clayart about cement fondue being a refractory cement
>and your reference that you used this type of cement when you cast your
>soda kiln. Could you give me some details on your kiln?? I want to cast
>a soda kiln this summer and have been reading Ruthanne Tudball's book on
>soda glazing and studying the kilns in there. How big is your kiln? What
>type of mix did you use and just how much did it take??? I have never
>cast anything before and have no idea how much it would take. Also, what
>type of burner system did you use? Any details that you can give me would
>be much appreciated! Do you have a web page? I would love to see some of
>your work!