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firing ramp for cone 6?

updated sun 21 nov 10

 

Judy Smith on sat 20 nov 10


I am having problems with one of my glazes bubbling. I wanted to try Ron's
suggestion "let the final temperature drop 100F and hold for a period of
time (start at 15 Min)". The problem is that I don't know what the firing
ramp of a typical cone 6 oxidation firing should be. I know how to use the
vary fire of my Bartlet controller because I experimented a little with
crystalline glazes. Can someone tell me what they use for each of the
segments of their cone 6 firing schedule?

Thanks,
Judy Smith

John Hesselberth on sat 20 nov 10


Hi Judy,

The firing schedule we currently recommend can be seen here:

http://www.masteringglazes.com/Pages/faqframe.html

The one published in MC6Gs is slightly different in that we suggest you =3D
set your kiln to drop at 500F/hr on its way down to 1900F. Mostly we =3D
just want it to drop quickly.=3D20

If you want to try Ron's suggestion I would just turn program the kiln =3D
to drop 100F at a 250-500F/hr rate. Then hold for 15-30 minutes. You =3D
just want to get it low enough that any off-gassing has stopped but the =3D
glaze is still plenty fluid. Then give it some time to heal.

Regards,

John

On Nov 20, 2010, at 7:06 AM, Judy Smith wrote:

> Can someone tell me what they use for each of the
> segments of their cone 6 firing schedule?

William & Susan Schran User on sat 20 nov 10


On 11/20/10 7:06 AM, "Judy Smith" wrote:

> I am having problems with one of my glazes bubbling. I wanted to try Ron=
's
> suggestion "let the final temperature drop 100F and hold for a period of
> time (start at 15 Min)". The problem is that I don't know what the firin=
g
> ramp of a typical cone 6 oxidation firing should be. I know how to use t=
he
> vary fire of my Bartlet controller because I experimented a little with
> crystalline glazes. Can someone tell me what they use for each of the
> segments of their cone 6 firing schedule?


Judy,
If you haven't already, get and carefully read John & Ron's book "Mastering
Cone 6 Glazes". Included is a suggested firing schedule for getting the mos=
t
from your glazes.

On John's web site, he has the presentation he gave at NCECA 2004.
Here's the link: http://www.frogpondpottery.com/nceca2004/p01.html

Understanding how and why you program a specific firing schedule to achieve
the best glaze development can often help you to understand and resolve
glaze problems.

A typical ^6 firing can be heated fairly quickly, but you must slow the
heating ramp as you approach top temperature, usually the last couple
hundred degrees. Slowing to about 125F per hour, then when top temp is
reached and cane has bent properly, holding for 15 - 30 min, dropping temp
to 1900F, then slow cooling, 125F per hour down to about 1500-1400F.

Bill

--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com