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wood kiln/soda question

updated sun 14 feb 99


Mark on fri 12 feb 99

I have been researching kilns and am interested in making the Olsen wood
kiln. Has anyone modified one for soda firing? If so, has it worked well,
how did you modifiy it and how are you putting the soda into the kiln?



Tracy Dotson on sat 13 feb 99

Mark...I haven't fired an Olson fast fire in a long time but the introduction
of soda into a kiln is accomplished in two ways. The first and most used way
is to dilute the soda in water and spray it into the kiln and on to the pots
(this means you need alot of spray ports to get good coverage). What I do is
to place salt in a section of angle iron (2X2X1/8 inch with the lenght long
enough to reach the back wall and have enough to hold on to when you dump the
mixture) I cover the salt with a hand full of soda and then a hand full of
borax and the wet all of it before stoking. I think I get brighter colors
with adding soda to the salt. Soda does not vaporize like salt and it you
dump it into the fire box dry it will just sit there and not circulate
throughout the wares. Good luck Tracy Penland NC

Gail Nichols on sat 13 feb 99

Do you mean the "fast fire" design? I built a small one of this type last
year---I think the design was in an issue of Ceramic Review---which could be
fired with oil or wood. I started the firing with wood, then switched to
oil at about 500-600C. A larger firebox is needed to fire it totally with

Anyway, I put my soda mix in through a port in the side wall of the kiln, up
at the end farthest from the chimney, in the space where the flame turns up
from the bottom of the kiln and moves into the chamber above. Worked fine.
It was a good little kiln.

Info on my soda technique---how I put soda into the kiln, etc.--is available
on my website:

Hope this helps.

Gail Nichols
Sydney, Australia
email: OR