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soft brick/hard brick, some of each?

updated sat 19 oct 02

 

Donna Sparks at Almost Art on wed 16 oct 02


At our studio all our home built kilns(4) have hard brick floors and some
have soft brick otherwise. We are looking at a commercial kiln as a
complement to our ancient array, it is all k23 softbrick and we are
concerned about how the 'vertically disadvantaged' of us will be able to
load the back stack without damaging the soft brick floor. (How) Do any of
you manage this?

When we suggested a hard brick floor, the response from both the
manufacturer and a knowledgable and trusted advisor was 'THE TWO DON'T
MIX'. Opinions on this? We can vouch for the fact that the kilns don't
fall down, and they fire pretty evenly for the first 20 years or so. Are
we losing a lot of fuel efficiency?

Gail Dapogny on thu 17 oct 02


In our guild, we place a board over the vulnerable brick floor area in
front of where we are stacking. In the beginning before you are used to
it, you will probably have to remind yourself that it is there so you don't
trip.
---Gail


>At our studio all our home built kilns(4) have hard brick floors and some
>have soft brick otherwise. We are looking at a commercial kiln as a
>complement to our ancient array, it is all k23 softbrick and we are
>concerned about how the 'vertically disadvantaged' of us will be able to
>load the back stack without damaging the soft brick floor. (How) Do any of
>you manage this?

Gail Dapogny
1154 Olden Road
Ann Arbor, MI 48103-3005
(734) 665-9816
gdapogny@umich.edu
http://www.silverhawk.com/ex99/dapogny (single historical photo - no longer
registered with Silverhawk)

Marjorie on thu 17 oct 02


Morning: A piece of plywood at least 5/8" thick and the size that will fit
between flu channel (if you have that) or the size of your kiln shelves.
Kneeling or with one foot on while you lean forward with the shelf you are
placing, plywood helps distibute the weight. Caution: don't forget to take
it out before you close/brick up the door, or you will be wondering about
that smoky smell early in the firing. Marj B


----- Original Message -----
From: "Donna Sparks at Almost Art"
To:
Sent: Wednesday, October 16, 2002 1:56 PM
Subject: soft brick/hard brick, some of each?


> At our studio all our home built kilns(4) have hard brick floors and some
> have soft brick otherwise. We are looking at a commercial kiln as a
> complement to our ancient array, it is all k23 softbrick and we are
> concerned about how the 'vertically disadvantaged' of us will be able to
> load the back stack without damaging the soft brick floor. (How) Do any
of
> you manage this?
>
> When we suggested a hard brick floor, the response from both the
> manufacturer and a knowledgable and trusted advisor was 'THE TWO DON'T
> MIX'. Opinions on this? We can vouch for the fact that the kilns don't
> fall down, and they fire pretty evenly for the first 20 years or so. Are
> we losing a lot of fuel efficiency?
>
>
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John Baymore on fri 18 oct 02



We are looking at a commercial kiln as a
complement to our ancient array, it is all k23 softbrick and we are
concerned about how the 'vertically disadvantaged' of us will be able to
load the back stack without damaging the soft brick floor. (How) Do any =
of
you manage this?

When we suggested a hard brick floor, the response from both the
manufacturer and a knowledgable and trusted advisor was 'THE TWO DON'T
MIX'. =



Gee...... I've been building kilns commercially for potters and
institutions for about 25 years.... and have been mixing hard brick and
soft brick all that time. Guess I better go back and rebuild them .

Seriously..... you can combine the two quite nicely. There are some mino=
r
considerations... like the different expansions of the two....... but it =
is
a pretty negligable issue. I've got kilns in heavy production use from 2=
5
years ago that have this configuration....... no problem.

For the "working floor" of most fuel kilns I build the surface is either =
2
1/2 inches of hard brick or something like Greenlite 28 as a top course. =

Behind this working surface is ALSO then adequate graded IFB layers to
bring the wall insulation value up to an appropriate value. =


One "trick" you might look at is to add a layer of thin splits or splits =
of
high duty hardbrick on top of the IFB layer on the existing kiln.... to
prodive a very durable surface that takes the mechanical abrasion of feet=
,
corners of shelves, dropped stuff, and so on..... plus to resist the drip=
s
of cone packs, glazes and "kiln disasters" . Yes... you'll lose about=
1
to 1 1/2 inches of stackable space.

Another approach would be to cut a sheet of 3/4 plywood to "fit" tha floo=
r
of the kiln where you need to work while you are loading the back bungs o=
f
shelves. Take it out when you start on the front.

Hope this is of help.

Best,

..............................john

John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA

603-654-2752 (s)
800-900-1110 (s)

JohnBaymore.com

JBaymore@compuserve.com