search  current discussion  categories  kilns & firing - salt & soda 

salt kiln advice - again

updated sat 24 jan 98

 

RothSmith on fri 16 jan 98

I've chosen the shelves -- silicon carbides from New Castle Refractories.
I've lined up a welder. I've arranged for someone to come help me build the
kiln. And now, after weeks of pussy-footing around, it is time for me to
actually order the bricks for my new salt kiln, and I am getting cold feet
about my plan to use softbrick and ITC (or some other zircon-based coating).
I've got a LOT of faith in Nils Lou -- and he says it should work. But I have
also been hearing about problems with that combination in salt.

So here is my question:
If YOU were building a salt kiln -- one that you hoped to fire as your primary
kiln over a period of years -- would you build its interior of hardbrick with
insulating brick outside? Or would you opt for greater fuel savings and go
with softbrick/ITC (at least in the lower-stress areas)?

Thanks!
Nan Rothwell
221 Pottery Lane
Faber, VA 22938

Grimmer on fri 16 jan 98

Nan,
Having only built salt kilns from hardbrick while in school, you can
take my advice with a grain of same (no, not brick!). I don't even
have any numbers to back up my opinion. Anyway.
Every salt kiln that is fired regularly will eventually need to be
torn down and rebuilt. If you get even half the life out of IFB, I
would venture to guess that your savings in fuel and time would
more than make up for the cost of rebuilding with expensive brick.
Just a guess.

steve grimmer
marion illinois

RothSmith wrote:
>
> ----------------------------Original message----------------------------
> I've chosen the shelves -- silicon carbides from New Castle Refractories.
> I've lined up a welder. I've arranged for someone to come help me build the
> kiln. And now, after weeks of pussy-footing around, it is time for me to
> actually order the bricks for my new salt kiln, and I am getting cold feet
> about my plan to use softbrick and ITC (or some other zircon-based coating).
> I've got a LOT of faith in Nils Lou -- and he says it should work. But I have
> also been hearing about problems with that combination in salt.
>
> So here is my question:
> If YOU were building a salt kiln -- one that you hoped to fire as your primary
> kiln over a period of years -- would you build its interior of hardbrick with
> insulating brick outside? Or would you opt for greater fuel savings and go
> with softbrick/ITC (at least in the lower-stress areas)?
>
> Thanks!
> Nan Rothwell
> 221 Pottery Lane
> Faber, VA 22938

Kenneth D. Westfall on sat 17 jan 98

Nan
In my book coatings are coatings and I have never seen one that didn't
fail sooner or later. Put your money into hard brick with a soft brick
insulation. Then coat the hard brick if you feel you need a coating.
There has been many old salt kiln built with hard brick so I can't see you
going wrong with hard bricks.
IMHO

Kenneth D. Westfall
Pine Hill Pottery
RD#2 Box 6AA
Harrisville, WV 26362
pinehill@ruralnet.org

DON'T GET STUCK IN THE MUDPIES--K & T

paul wilmoth on fri 23 jan 98

Nan,

I have built and fired quite a few salt kilns for colleges and myself. I
built a few with soft bricks that the brick manufactures said had enough
alumnia in them to allow the brick to repel salt. They worked great for
10 to 15 firing then they developed a layer of glaze which then proceeded
to peel off - leaving fresh exposed brick which did the same thing. After
a while there was no more brick left.
My best and longest lasting results are with hard brick on the inside and
insulated with k-20 bricks on the outside. My wood salt kiln is a
catenary arch and because there are always little creeper flames that
find cracks - I placed a layer of one inch thick fiber blanket between
the two layers and it has worked great for four years and about 20
firings. I don't think that I would do this any where other than an
arch because on the straight wall you will want to tie them together.
I have never used ITC but I have always thought that the best salted
pots came from a kiln that had interior walls that were salted and have
glazed themselves into one big monolith. A lot of those old ground hog
salt kilns lasted many many years!!!!

GOOD LUCK-- Paul