Judy Frederick on mon 29 mar 99
I bought a small used SNO Kiln recently. It is about 24" around and 24" high.
It runs in 10 amps. The bottom had a sheet medal with four bent brackets for
feet. The medal was rusting out. As I went to clean it up (with a vacuum),
it started to crumble. Actually it was not the sheet medal that crumbled, as
much as it was the layer of material underneath it. It was about one quarter
of an inch thick and was rusty black color. As I vacuumed it up, it just fell
away faster and faster. I unscrewed the sheet medal bottom which exposed this
material which was totally deteriorated. My vacuum collects the dirt in a
water reservoir. The contents in the water turned into a grainy rusty black
mud. I know I can get the sheet medal replaced, but does anyone know what the
other material was? What do I replace it with? Under that was the bottom of
the kiln, fire brick I think it is called. Should I just call a kiln repair
person, or is this something I can do myself? She said she had just replaced
the elements in the last few years.
TIA Judy in Baltimore
where it is supposed to be 70 degrees by mid week.
Euclid's Kilns & Elements on tue 30 mar 99
> Actually it was not the sheet medal that crumbled, as
> much as it was the layer of material underneath it. It was about one
quarter
> of an inch thick and was rusty black color...... but does anyone know
what the
> other material was? What do I replace it with?
Hi Judy,
It sounds like vacuuming was the best thing to do here. The material was
probably the sheet metal case, which swells & separates into layers over
time (moisture is absorbed). It may also have been asbestos, mineral fiber
board, transite board (concrete), or some other insulator which may have
also provided some strength to the base.
The cheap solution would be to buy some 2.5" K-23 bricks & place the kiln
on top. If the kiln is level...problem solved.
Your best bet would be to replace the metalwork on the bottom.
Chris @
Euclids Kilns & Elements
1-800-296-5456
euclids.com
mail @ euclids.com
David Hendley on tue 30 mar 99
I'm not familar with a SNO kiln, but here's what I did
with my Paragon, and I think it's a good way to go.
Forget about sheet metal. Why buy something that will
just rust out again? Go with steel. 1/4" plate. You can get
this, in whatever size you specify, from your friendly local
welding shop. If you are a handy do-it-yourselfer, you can
get the steel at a scrap metal yard, and cut it to size.
The 'other material' is some kind of fiberboard insulation.
My suggestion is to also forget about that.
Buy enough insulating firebricks to cover the steel plate
bottom. At 4 1/2" X 9" per brick, you won't need many.
Then set your kiln on this base.
This will provide much more isulation value than 1/2" of
block insulation.
For feet, you could have the welding shop weld on some
steel legs, or you could just use hard firbrick to raise the
bottom of the kiln 4 1/2" off the floor.
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com
Just read your second post. No, I would not use the kiln without
a base to hold the bottom together. Since you have a concrete
floor, you would probably be OK to not add the layer of firebrick
for extra insulation, but I would still recommend it, both for energy
savings and to slow down cooling of the floor after firing.
At 08:52 AM 3/29/99 EST, you wrote:
>----------------------------Original message----------------------------
>I bought a small used SNO Kiln recently. It is about 24" around and 24"
high.
>It runs in 10 amps. The bottom had a sheet medal with four bent brackets for
>feet. The medal was rusting out. As I went to clean it up (with a vacuum),
>it started to crumble. Actually it was not the sheet medal that crumbled, as
>much as it was the layer of material underneath it. It was about one quarter
>of an inch thick and was rusty black color. As I vacuumed it up, it just
fell
>away faster and faster. I unscrewed the sheet medal bottom which exposed
this
>material which was totally deteriorated. My vacuum collects the dirt in a
>water reservoir. The contents in the water turned into a grainy rusty black
>mud. I know I can get the sheet medal replaced, but does anyone know what
the
>other material was? What do I replace it with? Under that was the bottom of
>the kiln, fire brick I think it is called. Should I just call a kiln repair
>person, or is this something I can do myself? She said she had just replaced
>the elements in the last few years.
> TIA Judy in Baltimore
> where it is supposed to be 70 degrees by mid week.
>
Roger Korn on wed 31 mar 99
This is just a guess, but the nasty stuff was probably ceramic fiber or
asbestos
fiber board added for extra thermal insulation and the sheet metal was
probably steel
sheet metal, galvanized or otherwise. What happens is that repeated cycles
of heating and condensation causes the metal to corrode and the resultant
iron oxide breaks down the fiber
board, trapping more moisture and so on until it fails. When I build new
prototype kilns, I'll
use whatever I have handy for the outer shell, knowing that the life is
limited. For something you are going to keep and use over a period of
years, stainless steel will avoid the problem, since
it corrodes much more slowly, if at all.
Can you tell how thick the deteriorated layer was? If it's about an inch,
I'd suggest using Thermal Ceramics M-Board under the bottom and having a
sheet metal worker fabricate a 22-24 ga.
stainless pan for the bottom shell. The M-Board will run about $30 at your
pottery or refractory supplier (24" x 36" sheet) and the stainless pan
shouldn't be more than about $50 at a sheet metal shop if you take the kiln
in and have them do it "at their convenience".
Hope this helps,
Roger Korn
McKay Creek Ceramics
Box 436
North Plains, OR 97133
(503) 647-5464 after 6PM PST
rkorn@europa.com
----------------------------Original message----------------------------
I bought a small used SNO Kiln recently. It is about 24" around and 24"
high.
It runs in 10 amps. The bottom had a sheet medal with four bent brackets
for
feet. The medal was rusting out. As I went to clean it up (with a
vacuum),
it started to crumble. Actually it was not the sheet medal that crumbled,
as
much as it was the layer of material underneath it. It was about one
quarter
of an inch thick and was rusty black color. As I vacuumed it up, it just
fell
away faster and faster. I unscrewed the sheet medal bottom which exposed
this
material which was totally deteriorated. My vacuum collects the dirt in a
water reservoir. The contents in the water turned into a grainy rusty
black
mud. I know I can get the sheet medal replaced, but does anyone know what
the
other material was? What do I replace it with? Under that was the bottom
of
the kiln, fire brick I think it is called. Should I just call a kiln
repair
person, or is this something I can do myself? She said she had just
replaced
the elements in the last few years.
TIA Judy in Baltimore
where it is supposed to be 70 degrees by mid week.
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