Stuart Altmann on thu 20 nov 97
Every time I make large casseroles, I have the same problem: my lids don't
fit. This is not just a matter of random sloppiness, because the misfit is
always in the same direction: the lid is too large. Furthermore, I measure
both casserole and lid to the millimeter, and I check my measurements over
and over. Is this a common experience? Can anyone explain it?
Some information that may help:
1. I throw the body and the lid from the same wedged ball of stoneware
clay.
2. I throw the lid right side up. That is, I throw a torus of clay, then
pull the wall toward the center until it closes over, then throw the handle
from the excess clay in the middle. At the leather hard stage, the bottom
and sometimes the top are trimmed in a clay chuck.
3. Sometimes the body when dry is slightly asymmetric, having shrunk more
in one direction, so that it is wider in one direction than at right angles
to that direction. Yet, my lids are usually larger than even the long axis.
4. I make the lid (when wet) about 3 mm narrower than the top of the body,
so that there should be a small gap around it when it is seated on the body.
5. The bottom of the casserole is heavily compressed by the large flat rib
that I use to flatten and level it. Could this affect its shrinkage?
6. Are my tolerances unreasonable? Should one allow for a larger gap
around the lid of a larger casserole? My casseroles are typically 250 to
300 mm. Well, 2.5-3.0 mm is just 1% of that.
7. Last year, I made a large casserole from Laguna Clay's Big Pot, which is
a well-grogged throwing clay. The lid fit! Coincidence? Or does the
extra grog reduce not just shrinkage but variability in shrinkage?
Any ideas or advice will be appreciated! I'm getting tired of trying to
trim dry lid edges!
Stuart Altmann
David McBeth on fri 21 nov 97
Regarding Stuart's post about lid misfits...
Wouldn't heavy compression of the clay drive out some of the moisture
and thus result in less shrinkage?
--
David McBeth, MFA
Associate Professor of Art and Art Ed
330 C Gooch Hall
University of Tennessee at Martin
Martin, TN 38238
901-587-7416
http://fmc.utm.edu/~dmcbeth/dmcbeth.htm
Jan Lipuma on sat 22 nov 97
>----------------------------Original message----------------------------
the lid is too large. Furthermore, I measure
>both casserole and lid to the millimeter, and I check my measurements over
>and over. Is this a common experience? Can anyone explain it?
Stuart,
I was so glad to see your Clayart message re lids. I have been intending
to send the same question. I am having the same problem!!!:^(
Although a long experienced thrower, suddenly my casseroles are really
holding up production and completely wrecked my wholesale market this
season. I can't get the damn casserole orders out. Only about 1 in a set
of 5-6 will have a lid that fits by the time they are dry enough to trim.
I am throwing the lids upside down, adding the handle last. I don't think
either right side up or down is the issue. I think it is the clay body. I
have changed bodies from Standard 306 to Standard 153 - 306 was bad enough,
but 153 is impossible!! Unfortunately, it is all that is on hand at the
moment.
It works OK on boxes that are thrown in one piece, with a galley formed
with a straight vertical edge as the final throwing step, and sliced apart
later, but not on a two piece lid. The larger the lid/casserole -the worse
the problem.
I don't have any answers for us. I will change clay bodies AGAIN - can't
seem to find one I like for ^6 electric. Differences in thickness of lid
and casserole body, as Dannon suggests, might be factor, but.....the
difference is not very great at all. In fact, this last batch, I
deliberately tried to make them about the same thickness. still dried too
large.
This is a huge problem. Casseroles are a staple year round and I do a lot
for wedding presents in the summer, as well as the usual winter market.
I guess next, I'll try throwing them too small to start with. I would
appreciate your keeping me posted on any solutions you find. It did help
my psyche to see I was perhaps not the only lid collector around. luck to
us and the sooner the better. help...help.....help.....
Regards,
Janice Lipuma
Blue Moon Studio Pottery
Lexington KY
jlipuma@mindspring.com
Janice Lipuma
Blue Moon Studio Pottery
Lexington KY
TMartens on sun 23 nov 97
These posts made me feel better too. I am using the same clay and
same method I always have and suddenly the lids are drying too small!
At the leather hard stage the lids are a tight fit ( as I have always
done) and when dry they wobble around on the gallery.
Could us lid problem folk create an avant guarde market for those
damn lids? :)
Toni M
Jacquelyn Lumsden on wed 26 nov 97
>----------------------------Original message----------------------------
>Every time I make large casseroles, I have the same problem: my lids don't
>fit. This is not just a matter of random sloppiness, because the misfit is
>always in the same direction: the lid is too large. Furthermore, I measure
>both casserole and lid to the millimeter, and I check my measurements over
>and over. Is this a common experience? Can anyone explain it?
>
Hi Stuart-
I think the best invention for measuring any lids is the "Lid Master"
caliper. I have had a set for at least 10 years, and it still is in
perfect working condition. I always make the lids to fit exactly using
this caliper, and find that the lids seem to shrink just a bit more than
the pot part. I seldom have a problem with them too big or too small.
Robin Hopper suggested that the clay is stretched more horizontally and
therefore tends to snap back a bit more -- an educated guess.
When I make any lidded form, I generally make the hardest part first --ie
the part that has the flange. For me that is the lid of casseroles and
teapots as I prefer the casserole to have an open rim for cleaning and
serving purposes. I throw the lid, measure exactly and then throw the
bottom as it is much easier to adjust the uncomplicated edge than the
phlanged part. The "Lid Master" is also a boon to anyone who is asked to
make a new lid for a pot, as the second hole, marked 12 1/2 % will usually
give a good fit for stoneware. Just take the caliper apart and reinsert the
screw into the lower hole and measure the finished piece with the smaller
end. The larger end is the wet measurement.
Good luck.
Jackie Lumsden
in Ontario where winter is starting to make an appearance!
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