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which is the real cone 1?

updated sat 10 dec 05

 

Eleanora Eden on fri 9 dec 05


Hi all,

Below is an excerpt from Orton's web page. Notice that cones 1 and 2
show the same temperature in the small cones at faster firings.

----Temp. Increase Per Hour-----
Cone ---Large Cones---- ---Small Cones-----
Number 60C 108F 150C 270F 300C 540F
02 1101 2014 1120 2048 1148 2098 Yellow
01 1117 2043 1137 2079 1178 2152
1 1136 2077 1154 2109 1179 2154
2 1142 2088 1162 2124 1179 2154
3 1152 2106 1168 2134 1196 2185

I will soon be doing my first larger kiln firing at cone 1 and I know
that one of the issues has been the identical movement of cones 1 and
2 in the test firings.

Reading John Hesselberth's post today about firing slowly for glaze
development has focused my mind, and seeing this chart has explained
my findings.

Should I use large cones for best results? If I use large cones,
will the results be way different from test kiln results as the temp
is way different? If I stick to small cones since that is what I
have used in the tests, should I skip cone 2 altogether and use cone
3 for my guard cone? My goal is glazes with alot of interest, moving
away for the first time ever from decorating with designs and wanting
the glaze itself to provide the interest.

So that means firing slow. I fire my low fire kilns down at
100F/hour and then soak at 1600 -1650F for 40 minutes to an hour.
This is to give bubbles a chance to heal, and it is very successful.
So I assumed I would be following that same kind of schedule.

The kiln I am using for cone 1 is a much stronger kiln than my old
L&L, and smaller, so slowing down on the going-up side may be an
issue, it is not for my L&L because just getting there takes plenty
of time. Would I want the approach to be as slow as the fire-down?

My first larger cone 1 kiln will have my first Currie grids in it and
I am wanting to do the very best firing I can do to optimize those
results.

Thanks as always......here in the very snowy north..... and trying to
pay more attention to the headers before I send messages to
Clayart.......

Eleanora
www.eleanoraeden.com

Arnold Howard on fri 9 dec 05


Eleanora, I am not sure whether you are using small cones in the Kiln Sitter
or small witness cones.

In either case, I would use large witness cones. They are more accurate than
small cones in the Kiln Sitter, because the witness cones are right next to
the ware. The temperature at the Kiln Sitter may be slightly different than
at the shelf, and the Kiln Sitter could be out of adjustment.

I also prefer large witness cones to small ones, because they are easier to
see. The ultimate is self-supporting, because the 8-degree slant is built
into the base. They don't need cone holders, and the slant is always the
same.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com

From: "Eleanora Eden"
> Below is an excerpt from Orton's web page. Notice that cones 1 and 2
> show the same temperature in the small cones at faster firings.
> Cone ---Large Cones---- ---Small Cones-----
> Number 60C 108F 150C 270F 300C 540F
> 1 1136 2077 1154 2109 1179 2154
> 2 1142 2088 1162 2124 1179 2154
> I will soon be doing my first larger kiln firing at cone 1 and I know
> that one of the issues has been the identical movement of cones 1 and
> 2 in the test firings.
> Should I use large cones for best results? If I use large cones,
> will the results be way different from test kiln results as the temp
> is way different?