Tom Buck on mon 26 sep 05
Dan S:
Nylon is classified as a polyamide, that is, it consists of CO/NH
groups linked to C/H groups of the polymer (long-chain) molecule.
C=carbon; O=oxygen; N=nitrogen; H=hydrogen.
so when nylon degrades via high heat one of the combustion
products will be NOx, nitrogen oxide(s); the others will be H2O
(steam/water); and CO2, carbon dioxide, Carbon-4 Oxide.
The NOx is an acid gas, one of the gases of "acid rain" (other:
SO2/SO3). And yes, NOx will attack the Al2O3 layer on the kiln elements,
and MAY, if the presence of NOx continues long enough, to cause an element
failure.
But I would judge the penalty of using nylon to be minimal - a
cone 6 firing of Kanthal A-1 wire can continue for approx. 180 firings
with a typical claybody (gives off SOx, some NOx, some fluorides, all of
which take metal away from the elements). So some extra NOx may drop the
firings by 5%, to 170 firings.
If the use of nylon provides you with sellable pots, then
replacing elements for $300 (+ your labour) would certainly be
worthwhile... the nylon might make a difference of a month or two in say
two years of normal element life.
make great pots. peace Tom
Tom Buck ) -- primary address.
"alias" or secondary address.
tel: 905-389-2339 (westend Lake Ontario, province of Ontario, Canada).
mailing address: 373 East 43rd Street, Hamilton ON L8T 3E1 Canada
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