Firing Tmes

Hi Pete,

There are about as many firing cycles as there are glaze recipes. There is
no definitive answer, but have a look at my website
www.users.bigpond.com/dcoggins
for a few pointers.

Bisque temps for pottery are specified by the clay suppliers, usually at
least 1000C but not too high, as the glaze won't stick.

High bisque firings/ low gloss firings are used in slipcast ceramics - the
high bisque to vitrify the clay, and the low glaze temp to retain the bright
colours. Glazes for this method have lots of gums to make them stick to the
vitrified clay.

Main thing in bisque firing cycles is to control temp rise until moisture
and inorganics are gone, and silica is converted - usually red heat.

Hoe this helps a bit

Regards

Dave


"potty" wrote in message
news
Hi everybody
we've just acquired our first electric kiln with a good controller. I'm
a bit confused about firing cycles though as some articles recommend one
schedule, the controller manual recommends another etc etc etc. At
college all biscuit firings went to 1040ºC for both stoneware and
earthenware work obviously for the sake of standardising and this seemed
to work realy well but several sources (including the manual) advised
bisque firing to 1140/1180 for subsequent glost firings at around 1080 -
what's that all about.
I usually reference Hamers' Dictionary but no sample firing cycles are
included although good info on the specific stages are explained (as
they are on digitalfire's site.
Can anyone recommend a good publication including or specialising in
this subject or even give me some pointers.
Thanks in advance
Pete