Carla Flati on tue 4 dec 01
Hi Everybody!
I'm only about 2 months behind on my Clayart digests, but I've managed to
keep up with the last 4 or 5 days worth. I had to respond to Gillian's post
because I can't believe that Aardvark clay came up with such a lame-ass
explanation for something that in my opinion was Aardvark's mistake. In
fact, I'd bet my last pay check on it. This is what I think happened.
Clay manufacturers usually run batches of different clays by color. A cone
5 white clay may be mixed following a cone 04 white earthenware body. Now,
when you have a mixer feeding into a huge pugmill with a 15 ft. long barrel,
it's impossible to know where the earthenware stopped and the cone 5 begins.
It's not a matter of weighing out a certain amount of clay then mixing it,
pugging, bagging and boxing that exact amount of clay. It just doesn't work
that way. Where I work, the questionable clay is bagged, not boxed, then
loaded onto a pallet to be sold as "horse shoe pit clay". Sometimes as much
as a thousand pounds goes onto a pallet until the mixer (person, not
machine) is absolutely sure that the right clay goes into the right box.
Now, some companies may not want to scrap up to a thousand pounds of clay.
Maybe they discard a few 25 pound blocks and that's it. I think this is
what happened in Gillian's case because not even a cone 5-6 clay would look
like candle wax in a cone 10 firing. At least not the cone 6 clays where I
work. I know because I get to play mad scientist and I've tried them all.
With the exception of the C/6 grolleg porcelain (does sort of self glaze)
the cone 6 clays turned out to look like buttermilk biscuits all puffy and
bloated....definitely not melted. The scientific explanation they gave is
totally absurd. In fact, I bet the clay wasn't tested at all. The
explanation sounds like a canned answer. How would they explain a cone 10
iron bearing clay that is once fired in a reduction kiln......successfully,
time and time again. PUH LEESE!!
As a potter who has to play the devil's advocate on a daily basis by
answering technical questions, I am well aware that there a quite a few of
us who tend to blame the clay first but in Gillian's case, I would have to
say that the manufacturer made one big screw up. If I were Gillian, I'd
really be pissed at Aardvark and I would definitely let them know it.
Respectfully submitted by Carla the potter, not the technician.
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