Victoria E. Hamilton on thu 11 jan 07
Vaishali -
Here's a possible schedule for you:
1. Load kiln with bone-dry greenware
2. Junior 04 cone is placed in kilnsitter mechanism
3. With lid propped and the bottom switch on LOW, press the button on the
kilnsitter IN.
4. Soak overnight
5. In the morning, switch on your vent
6. Turn top and middle switches to low for 2-3 hours
7. Turn all switches to medium for 2-3 hours
8. Turn all switches to high, close the kiln lid and plug all holes but the
top one.
9. Turn the timer to 4-5 hours if the kiln is a small one - 10-11 hours if
the kiln is large.
10. Switch off vent.
11. Note all times and actions on a log.
12. When firing is complete, note time left on the timer on your log.
13. Cool for approximately 17 hours before cracking (prop lid & remove
plugs) the kiln.
14. Unload when you can handle the ware with your bare hands.
There will probably be many other schedules proposed.
I hope this helps.
Vicki Hamilton
Millennia Antica Pottery
Seattle, WA
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Vaishali Wagh
Sent: Thursday, January 11, 2007 7:39 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: [CLAYART] firing schedule and pyrometer
Hi everyone,
HELP! I recently bought a kilnsitter kiln with heat control switches. I will
be firing a manual kiln for the first time ever and am a bit overwhelmed and
daunted by it. Can someone give me an easy step by step firing schedule for
^04 bisque firing for high fire stoneware? I will use a junior ^04 cone in
the kilnsitter, and also have ^06 and ^04 cones that I can view through the
peephole.
I have an analog pyrometer which I have heard is a good thing to keep track
of heat rate, and was wondering if I could insert it into one of the
peepholes instead of drilling a hole for it. Is this a wierd thing to do?
Would the results be inaccurate because it does not fit snugly into the
peephole?
I am an absolute neophyte at firing, so any advice from clay brainiacs is
very welcome!
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Vaishali Wagh on thu 11 jan 07
Hi everyone,
HELP! I recently bought a kilnsitter kiln with heat control switches. I
will be firing a manual kiln for the first time ever and am a bit
overwhelmed and daunted by it. Can someone give me an easy step by step
firing schedule for ^04 bisque firing for high fire stoneware? I will use
a junior ^04 cone in the kilnsitter, and also have ^06 and ^04 cones that
I can view through the peephole.
I have an analog pyrometer which I have heard is a good thing to keep
track of heat rate, and was wondering if I could insert it into one of the
peepholes instead of drilling a hole for it. Is this a wierd thing to do?
Would the results be inaccurate because it does not fit snugly into the
peephole?
I am an absolute neophyte at firing, so any advice from clay brainiacs is
very welcome!
Snail Scott on fri 12 jan 07
At 10:39 AM 1/11/2007 -0500, you wrote:
Can someone give me an easy step by step
>firing schedule for ^04 bisque firing for high fire stoneware?
>I have an analog pyrometer...
Forget the pyrometer. They are handy for
some stuff, but unnecessary for this.
Skip it.
If you have been firing up to this point
using a programmable computerized kiln,
you have some bad habits of thought to
unlearn. All those digital readouts and
demands for ramp and hold schedules can
leave you thinking that such stuff is
actually necessary, and that a manual
kiln can't be properly fired without
similarly precise heating rates and
real-time feedback.
Pffffthththtt!!!
First, leave the lid propped slightly open
on a small brick, and push the 'on' button.
If the stuff might be damp, turn the top
ring to 'low' and let it run 'til it seems
dry. If it seems dry, turn all the rings
to 'low' for an hour, or more if it's
really, really thick. Then shut the lid
and leave it for an hour. Then turn the
knobs to 'med' for an hour. (This can go
lots quicker for a glaze firing.) Then
turn everything to high and wait for
a few hours or so. Check your cones. Wait
for the sitter to trip. (You want to find
out how it's calibrated, so let it turn
itself off this time, while you watch.
If the ^4 witness cone goes flat first,
turn it off manually.) Let it cool
overnight and unload. Compare the witness
cones with the sitter cone. If they
are close enough, fine. If not, you can
either recalibrate the sitter (easy, but
I won't explain here), or just compensate
by using a sitter cone that will match
up better with the witness cones.
Make more work, then repeat, etc. ;)
In a nutshell:
An hour (or more) on low with lid cracked.
An hour on low with lid shut.
An hour on medium.
Turn to high and wait.
Unload in the morning.
If for any reason you want a slower
bisque (thick, dense work; lots of
organic matter to burn out, etc): when
you turn the knobs to 'hi', leave the
middle one on 'med'. You will hit
bisque temperature just fine, and
pretty evenly, but much slower. It will
be unlikely that you'll need to do this,
though.
Keep it simple, and relax!
-Snail
Jennifer on fri 12 jan 07
Hi Vaishali,
I use a manual kiln and pyrometer.
I first learned to fire from Richard Zakins book Electric Kiln Ceramics =
and have never had a problem with ware breaking... all praise to the =
kiln gods and knock wood just in case!=20
I leave the top peep open throughout the firing & place my witness cones =
to be visible though it. I put my pyrometer probe in the second peep and =
leave it there. I guess you could alternately remove it and replace it =
and close the peep in between.=20
I fire on low with the lid propped open about 1 -2 inches for the first =
2 hrs, close the lid and leave the kiln on low 6 - 8 hrs (like =
overnight). When the pyrometer reads about 1000=BAF I turn the switches =
to medium and proceed still fairly slowly up to 1080=BAF to get through =
the QI state. Then I turn up to high and keep an eye on the pyrometer =
til it looks close to the temp I want, and start watching the witness =
cones for accuracy. Once the cone I want starts to bend I cut the =
swithches back to low for about 15 minutes for bisque.
Then let it cool to under 200=BAF before opening.
Also, you might want to chart the times and temps as you go so you have =
a guideline that works for your kiln.=20
good luck & happy potting,
Jennifer
3 miles west of Hell
Arnold Howard on fri 12 jan 07
I would contact the kiln manufacturer and ask for a drilled
peephole plug. They are designed for inserting a
thermocouple into the kiln. The drilled plug costs around
$4.75.
You can find firing schedules at Paragon's website that may
work for your kiln:
http://www.paragonweb.com/Instruction_Manuals.cfm
Scroll down the list of publications to firing schedules and
select A-66B for a 7-sided kiln, A-82B for an 8-sided kiln,
or A-24B for a 10-sided kiln. They are in pdf format.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
From: "Vaishali Wagh"
> I have an analog pyrometer which I have heard is a good
> thing to keep
> track of heat rate, and was wondering if I could insert it
> into one of the
> peepholes
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