search  current discussion  categories  glazes - cone 8-10 

cone 10 ox and questions, questions, questions!

updated sun 2 jul 06

 

Kitty on tue 27 jun 06


Hello everyone!

I'm relatively new to clay: roughly a year and a half now since I first
got muddy, and have been lurking for about half a year now.
This list, and all of you, is great! I've probably spent WAY too much
time absorbing the archives in researching one after
another crazy idea that I wanted to "mad scientist" experiment with. So
much to know, so little time!

Which leads me to my first clayart question, and it's all John Britt's
fault! (those pretty pretty oil spot glazes!)
I'm wanting to try out the cone 10 oil spot glazes, but the school I'm
at is currently between instructors. The instructor I started
with retired end of last semester...he started our clay program 2-3
decades ago. This leaves me to my own devices to gather
information...a wonderful last lesson for the would-be pottery career!
(gulp!)
I have 2 options for firing to cone 10 at my disposal: a 30-cubic foot
(dual burner) natural gas car kiln and my personal 7-cubic foot
Skutt KS-1027. I would prefer to use my kiln, as I don't think I could
handle botching a 30 cubic foot glaze test. This leads me to
2 major issues I can't find answers to on my own.
1: I understand that firing to cone 10 in an electric is hard on the
elements, especially since my Skutt is 2.5" brick with standard
Kanthal elements instead of the beefy Kanthals. I couldn't find an
estimated number of cone 10 firings for the elements, though.
Any ideas on how many high firings I could get before having to replace
them all? I've only fired the kiln 3 times: the empty 04 to
prep it, an 06 bisque, and a 6 glaze. It's just at a year old.
2: I've been using the kilns at school for the most part (why I haven't
fired mine hardly at all), but those are electronic KilnMasters,
where mine is a manual KilnSitter. I finally got the hang of
programming schedules around the turn of the year, but I've been told I
can't use the school Skutts above cone 8 due to the accelerated element
wear. (Two-year program with 16 pottery students at any
given time, and as many assignments and shows as we dare.) Err...how on
earth do I control the firing with a manual kiln, especially
when I get to the part where I have to slow down to around 30F an hour
(estimated for 3 hour climb from cone 7 to 10...is that right?
sneaky 3rd question!)

Oh, fine: question number 4: If I do this in the gas kiln...how do you
do control the firing in oxidation? I've only done 2 gas firings, both
reduction, set at either 04 or 06...the reduction took care of slowing
the kiln for me, and equalizing was done by pushing the
damper a little and unplugging the coldest peephole.

Thank you for putting up with yet another pesky student who has nothing
but questions!


~Kitty
in western NC, just east of Asheville.

Kitty on sat 1 jul 06


Thanks to everyone who replied. I'm ordering a pyrometer within the week.
With what's been suggested, I'm starting to be glad I got the kiln
sitter model instead of the electronic after all.
They say the best time to develop good habits is from the start, and
this forces me to keep a close eye on the kiln...no chance of being
tempted to just let it "do its thing."

Snail: Thanks for the gas oxidation info: As soon I get the hang of
this glaze in the electric kiln, I'm going to put your information to
use! I'll take it from the beginning again, though...slow and careful
steps keep the kiln shelves nice, right?

~Kitty