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thermal shock,whiteware/pilot error

updated wed 15 feb 06


Vince Pitelka on tue 14 feb 06

Mel wrote -
> make sure it was not customer error.
> it happens all the time. your clay may
> be perfect.

This is such an important thing to consider. A professional potter must at
once be confident of their product and yet open to the possibility of flaws,
because you never know when they will appear. Ours is not an industrial
science in the clay studio, and we especially cannot control the quality of
raw materials we start with, so we never know when a flaw might rear its
ugly head.

That said, it is absolutely true that the customer will sometimes mistreat
their pottery and then blame the maker for any problems. Mel's mention of
the granite countertops is a good example. I don't like granite counters
because they are so cold and hard - they just seem unfriendly in a kitchen -
and because the coarse-grained versions compete visually with the utensils,
pottery, and food. Why in the world would anyone want that? But back to
the subject at hand. The granite and soapstone countertops are celebrated
for being heat resistant - you can take a pot out of the oven and set it on
the countertop. Yes, the countertop won't be damaged, but if the pot is a
flat-bottomed hand-made ceramic piece, it will likely crack from the sudden
thermal shock.

Here's a good example of customer misuse and misdirected blame. In my
studio in Northern California back int he 70s and 80s I made lots of large
slip-decorated, feather-combed platters
( Most
people hung them on the wall, but they were certainly fully functional as
well, if used with proper care. One particularly good customer prepared a
salmon baked on a large cookie sheet. She removed it from the oven, and
with several large spatulas transferred it directly to one of my platters
with no pre-heating or other preparation. She immediately carried the
platter into the dining room and set it down in the center of the table to a
chorus of "oohs" and "aahs" from her admiring guests. The platter responded
with a resounding "CRACK" as the salmon juices spread out across the
tablecloth. It kind of spoiled the moment.

The customer called me later that evening and she was LIVID. I gave it back
as good as I got it, and scolded her soundly for her lack of common sense.
I said "What did you THINK would happen if you put a big hot fish in the
center of a cold ceramic platter?!" As mentioned, she was a very good
customer, so I agreed to replace the platter just that one time. She
continued to be a very good customer.
- Vince

Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111,

W J Seidl on tue 14 feb 06

Regarding Mel's post earlier replying to Jennifer regarding customer
error/whiteware, and thermal shock.

A public thanks, Mr Mayor. Many of us here have recently had to replace
kitchens due to flooding, myself included. While we were already in the
practice of placing hot oven items on a trivet or potholder to guard =
burning of a laminate countertop, it never occurred to me to have to =
against thermal shock with the new granite. My kitchen people when =
told me that not only can the pot crack, but also the counter, being =
1/2 inch thick. I was surprised to say the least. (I know I know, but =
you think of granite, you think "impervious" and "indestructible", or at
least I did.)

When I asked why they didn't warn people about that, I got a grin and =
comment "Better for business".

I think that fact is going to make foot rings and feet on bowls and pots =
lot more desirable in the near future (hint, hint).

So thanks, Mel, for educating the oblivious.

Wayne Seidl=20