William Lucius on mon 12 jan 04
We use a two channel pyrometer (thanks to the ClayArt post that =
suggested Omega). In other words, it has two pyrometer wires that can =
be placed in different parts of the pit. We hook it up to a lap top =
computer so that we can see the firing progress in real time. It is =
nifty but I would echo the point that you should protect the pyrometer =
wires with tubes, otherwise plan on replacing them regularly. We also =
use a plywood shield to protect the pyrometer and computer from the =
radiant heat (when it starts charring you know that you have a hot =
fire).=20
We are taught in archaeology to make sure that you know what it is you =
are measuring. Merely knowing the temperature does not really equate =
with cones, since a cone measures something like work energy, which is =
quite different than momentary temperature measured by a pyrometer. Our =
pit firings rarely last 3/4 of an hour, and the pyrometer merely tells =
us the heat rise and maximum temperature where the probe is located. =
And pit kilns are notoriously variable from top to bottom and side to =
side, and are affected by wind, rain, hail, fuel type, fuel placement, =
pot placement, pit depth and the potter's competence. As an =
archaeologist we use the pyrometer to accumulate data, but as a potter I =
would use a pyrometer to develop a consistent firing procedure. That =
is, if I could reasonably replicate the firing curve and final =
temperature over a series of firings I would consider the cost and =
effort of a multichannel pyrometer worthwhile. However, you could =
accomplilsh the same goal without the technology.
William A. Lucius
IACR
iacr@msn.com
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