C Newlin on sun 5 jan 03
Hello there.
I could use some suggestions on how to prevent greenware warping during
drying. I'm making some tiles, 8" to 14" square, with projections coming
sticking out on both the front and back of the tiles and I am not finding
much help in my books on how to prevent them warping.
Since they cannot be laid completely flat, or be sandwiched between boards,
I'm not quite sure what to do. Would it help to dry them on edge?
Any suggestions are really appreciated!
Thanks...
Mike Gordon on sun 5 jan 03
Hi,
Yes, drying them on edge will help as I don't see any other way around
it with projections on both sides. How do you plan to mount them? Mike
Gordon
Dawn Christensen on sun 5 jan 03
HI
A few months back I asked the list about drying large slabs and got
some good advice from Snail and others. It was suggested that I dry them on
drywall. They can be stacked but must be rotated. I also placed plastic 2"
strips around the edges so the thought they were drying from the inside out.
It was also suggested (after I started) that you could paint the edges with
latex) This sounds good and I would have tried it if they hadn't been in
process. I cut them at 16" and lost between a 1/2 " to 1" on opposing sides.
I also cut 16 squares to get 12 good ones, and I made some paper clay out of
the same clay body for repair. I flipped the squares every morning and
evening and left the top pieces of drywall off when I was in the studio. It
was a challenge. I have not cared for something so much since my children
and dog were young. It was suggested that I fire these vertically but I was
worried and fired the first 4 horizontally on sand. I also reprogramed the
kiln to climb by 50 degree increments, soak, and cool slowly. I did place a
shelf on top to shield them when I opened at 300'. By the end of this firing
I was impatient. It took almost 18 hours to cool to a safe temperature to
open. The next firing I went vertical and got all the rest of the tiles in
one firing. There was not much difference except that I was done instead of
firing all week. I had a few cracks but not all the way through and ones I
could deal with. I learned a lot doing these pieces and was grateful to the
many people on this list who shared and encouraged me. In the end I smoked
them and drew on them with pastels. I built frames to display four as one
piece and used liquid nail to mount them. I hope some of this information
helps. Another person on this list and I forget the name or I would credit,
mentioned using refrigerator shelves. I thought this was a good idea also.
Think flat, rotate, look for ways to circulate air and keep them out of
drafts. Good luck, Dawn
Jeremy McLeod on sun 5 jan 03
C Newlin wrote:
> I'm making some tiles, 8" to 14" square, with projections coming
> sticking out on both the front and back of the tiles
Hmmmm. "Projections"? I'm wondering if one side of the tile
has fewer "Projections" than the other and if they are localized
enough so that a drying board could have holes cut into it to receive
the "Projections" so that most of the tile could be resting on flat, absorbant
material like wallboard.
???
Jeremy McLeod
Snail Scott on sun 5 jan 03
At 12:53 AM 1/5/03 -0600, you wrote:
>I'm making some tiles, 8" to 14" square, with projections coming
>sticking out on both the front and back of the tiles and I am not finding
>much help in my books on how to prevent them warping.
>Since they cannot be laid completely flat, or be sandwiched between boards,
>I'm not quite sure what to do...
Try making balls of clay, and setting them on
all the low spots of the tile. The more you
use, the better it works. Then, put the boards
across. Wrap up well, since you don't want the
air gap around the bumpy side to cause faster
drying. Flip over and swap out the bottom
wallboard now and then, to help it dry evenly.
-Snail
Jim Murphy on sun 5 jan 03
Hello "C",
Not sure from your info what type of clay you're using or what
size/shape/number of projections on each side you're dealing with, however,
I'll go ahead and offer a few suggestions:
1. Go ahead and try drying "on edge" - could be trouble though depending on
clay body, tile edge thickness, projection size, etc.
2. Try using a different clay body to prevent warping. Perhaps one
incorporating Kyanite which may provide better mechanical strength due to
its interlocking particle-shape.
3. Make your tiles differently. Make 2-halves separately - each with flat
bottom and top projections. Dry both halves separately to leatherhard stage
with flatside "down". Score both flat "bottoms". Apply clay slip made from
same clay body and "sandwich" two halves together. Could work or could open
up a whole new can-of-worms.
Something to think about.
Good luck,
Jim Murphy
Dean Walker on sun 5 jan 03
If you could slow down the drying time by wrapping them loosely in light
plastic it might help.
Dean
Paul Brinkmann on mon 6 jan 03
Dont make to many tiles with reliefs on both sides, but when I do, I sandwich
them between sheet rock, and 1/8 inch foam rubber. You could use thicker
foam rubber if necessary, but this system seems to work for me.
PGBrinkmann, from the City of Saint Anthony. {San Antonio, Texas}
LindaBlossom on mon 6 jan 03
I find the idea of projections from boths sides to be interesting. I assume
these are not tiles to be installed as tiles usually are. You didn't say
anything about your clay body so that is where I will go. I believe that
the starting point for all questions regarding tiles and warping is the clay
body. I tested many clay bodies when I first started and found that most
throwing clays warp. I have made my own clay now for several years and
rarely see a tile warp and I usually dry them on a metal shelf over a wood
stove .or in the sun in the summer. I just don't feel it is worth it to
fight the wrong clay body. A tile clay, imho, should contain a lot of grog
and course clays like fireclay.
Linda
Ithaca, NY
> Hello there.
> I could use some suggestions on how to prevent greenware warping during
> drying. I'm making some tiles, 8" to 14" square, with projections coming
> sticking out on both the front and back of the tiles and I am not finding
> much help in my books on how to prevent them warping.
> Since they cannot be laid completely flat, or be sandwiched between
boards,
> I'm not quite sure what to do. Would it help to dry them on edge?
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