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salt/soda shelves

updated sat 10 jan 98

 

Mmpottery on mon 22 dec 97

Hi out there! I'm getting ready to fire my salt kiln for the first time. I
did alot of salt 15 years ago but not since. I'm trying to decide whether I
should :
A- Not use shelves at all
B- coat them with Alumina/Silica wash (or was it Alumina/EPK)?
C- not coat the shelves and use waddies under the pots with the
same kiln wash mixture I can't remember......
Does anyone have thoughts about this??????
Thanks alot and MERRY CHRISTMAS!!!!!!
Michelle

Mark Issenberg on tue 23 dec 97

Hey there, A couple of weeks ago I was salt firing ay the U.Miami.We
used 50% epk 50%alumina hydrate for wash and the same for wadding. If you
wad early use Elmers glue on each wad. I thought that was pretty cool ,
It works great. That way the wads dont fall off when loading , you learn
somthing new once in a while Also I still am looking for a
cannon to fire and also a bell I dont know why I just want one probably
something about boys and toys. And I still have a Alpine
24 for sale ,if any of you are around help me pick pink grapefruits.
Mark
in Miami

paul wilmoth on tue 23 dec 97

Michelle,

You can do a number of things.!
1)you can sprinkle dry alumnina and put your pots on the powder. This is
good because it is a better support for flat works and the warp less that
when you use wads

2) Do the same with silica - it works as well as alumnina and is cheaper,
because it is not "with" any other material it will not flux into glass,
it will (as does the alumnina) become a bit crusty when the salt hits it,
but because it is not in a state of vitrification it will not bond with
the salt!

3) Use nothing one the shelves and use wads (3/4alumnia,,1/4kaolin)

4) If you ever want to flip your shelves (and you will) do not " wash"
the shelves. This is where the dry powder works great because it comes
off with no problem. The powder does not fly around and land where you
do not want it, but you need to be careful in loading that you do not
brush any down on pots below. Keep the powder at least 1/4 inch away from
the edge of the shelf. To save on silica or alumnia I place the pot where
I want it, then draw a pencil line around the foot , remove the pot and
lay down 1/8 inch of powder and place the pot on it. This allows for some
salt (from the well salted shelf) to give a residual salting to the
underside of the peice. Other wise you do not get any salt where the
powder seals off the foot.

I use a combination of powder and wads thoughout my kiln, wads for vases,
pitchers etc. and powder for flat pots so they don't warp!!

Good Luck -- Paul W

THE POTTER on thu 25 dec 97

We both wad and use a wash. Wadding is Alumina Hydrate 8, China Clay 4,
Bentonite 1, Grog 1. The wash is Alumina mixed with polymer wall paper paste
to keep it in suspension. Alumina 9lbs in 12 pints of paste. Flour pastes
are no good as they become ineffective when the flour goes off. After the
firing the I stack shelves flat with slats in between so that the load goes
down vertically shelf /slat shelf/ slat to the floor. This is to stop any
slightly warped shelves from being broken. you can use the shelves several
times before rewashing. Underneath I brush a strip of Acme marls batt wash
where the props touch. We have used lime over alumina when the firing was
lower but this was unpleasant to work with and you could use Quartz gravel
on the wash in place of wadding. Shelves or not ? what finish do you want?
The shelves come apart whatever, worse now than before. Try to get shelves
from a heavy pressing for greater density. After years of wrecking them I am
tending towards deigning to do without but it still has to pass the
customer.
Mmpottery wrote in message <73cb4ad5.349e831b@aol.com>...
>----------------------------Original message----------------------------
> Hi out there! I'm getting ready to fire my salt kiln for the first time.
I
>did alot of salt 15 years ago but not since. I'm trying to decide whether I
>should :
> A- Not use shelves at all
> B- coat them with Alumina/Silica wash (or was it Alumina/EPK)?
> C- not coat the shelves and use waddies under the pots with the
>same kiln wash mixture I can't remember......
> Does anyone have thoughts about this??????
> Thanks alot and MERRY CHRISTMAS!!!!!!
> Michelle

Ann Zerger, Associate AIA and Chip Parker, AIA on thu 25 dec 97

Mmpottery wrote:
>
> ----------------------------Original message----------------------------
> Hi out there! I'm getting ready to fire my salt kiln for the first time. I
> did alot of salt 15 years ago but not since. I'm trying to decide whether I
> should :
> A- Not use shelves at all
> B- coat them with Alumina/Silica wash (or was it Alumina/EPK)?
> C- not coat the shelves and use waddies under the pots with the
> same kiln wash mixture I can't remember......
> Does anyone have thoughts about this??????
> Thanks alot and MERRY CHRISTMAS!!!!!!
> Michelle

I use a thin dust layer of flint on shelves to prevent pieces
sticking, works great, also small pea wad of pure kaolin under lids or
under pots works great. The flint protects your shelves. You should
only use silicon carbide shelves designed for salt fire. New Castle
Refractories is where is get these.

Good luck , Anny

paul wilmoth on fri 9 jan 98


I have fired salt for quite a few years and I have never used quartz
gravel. I am a bit interested in using the quartz gravel. Are there any
draw backs to using it? Can you still stilt shelves , as long as it is
sturdy? And where do you purchase the quartz gravel?

Thanks - Paul