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Kiln Setter cones
These cones control the Kiln Sitter it'self. When the heat gets to the proper temp. these cones bend, in the sitter, allowing the sitter to drop and turn off the kiln.
Kiln Sitter cones come in three different styles. All are good, just some people prefer one over the others.
Orton Jr. is shaped similar to the Tester cones. It is larger at one end than the other. Good, especially if you have more than one kiln. You can adjust the bar to either the narrow end, if your kiln is firing hotter, or to the wider end, if your kiln is firing cooler.
The triangle bar is also a popular bar. It is the same width, all the way across, in a tirangle shape.
Then there is the bar cone. This cone is completely the same on all four sides.
They all work the same way, you will find that you like one over the others.
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Orton Cones
There are several types of cones
For ceramics, kilns are not fired just to a temperature.
They are fired to a "cone" level, which accounts for time as well as temperature.
Think of it as heat absorption rather than just temperature.
Cones come in different numbers,
eachnumber corresponds to a heating-rate/temperature-combination
which will make that cone bend.
At the beginning of the firing the cone is standing at an 8 degree angle.
A perfectly fire cone tipwill be bent to a 90 degree angle.
If the cone is bent less, the kiln was under fired.
If the cone is bent more, the kiln was over fired.
The tip of the cone on an SSB should be with in the base
of the cone for a perfect firing.
All cones are numbered. The hottest is 10, going down to 1.
Then as the required temp continues to get cooler
the cone numbers continue to reduce -01, 02, etc.
So there is a BIG difference between cone6 and cone 06.
The 6 being the hotter of the two, is used for Porcelain Greenware,
while the 06 is used for ceramic glazes.
It is recommended, that youput a tester cone in your kiln
every time you fire it,
especially if you are firing for the general public, or firing utility pieces to sell.
This is the only way you know exactly whatyour kilnis doing.
Your kiln is like an appliance in that things can go wrong without your detection,
unless you have the tester cones sitting on your shelf to tell you.
Cone number |
Orton Cones
Final temp in degrees F at ramp rate of 27 degrees F/hr |
Orton Cones
Final temp in degrees F at ramp rate of 108 degrees F/hr |
Orton Cones
Final temp in degrees F at ramp rate of 270 degrees F/hr |
Type of work done at these temps |
In standard firing, cones of the correct number are placed around the kiln and are watched. When the cones fall the kiln is turned off. This works the same for gas and electric kilns.
Electric kilns with electronic controllers (such as the Skutt KilnMaster series) have a thermocouple which continuously measures the temperature, records it over time, and shuts off the kiln when the appropriate heat absorption has been met. So if the ramping temperature is fast, the kiln will go to a higher temperature before it turns off than if the ramping temperature is slow (thus allowing the clay to absorb more heat along the way.) The final temperature is most affected by the rate of temperature increase over the last 300 to 400 degrees of firing.
Note: Think of the 0 in a cone number as meaning "minus". So 06 is much cooler than 6 because it is like a "minus 6".
Typcically it takes 15-25 minutes for a cone to bend once it starts. This depends on the cone number. The cone bends slowly at first but once it reaches the half way point it bends quickly. When the cone tip reaches a point level with the base, it is considered properly fired.
If a cone is soaked at a temperature near its equivalent temperature, it will continue to mature, form glass and bend. The time for the cone to bend depends on several factors and as a general rule, a 1 to 2 hour soak is sufficient to deform the next higher cone number. A soak of 4 to 6 hours will be required to deform two higher (hotter) cones.
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10 |
2284 |
2345 |
2381 |
High Fire Ceramics |
9 |
2235 |
2300 |
2336 |
8 |
2212 |
2273 |
2320 |
7 |
2194 |
2262 |
2295 |
Mid Fire Ceramics (Cone 5-6 most common) |
6 |
2165 |
2232 |
2269 |
5 |
2118 |
2167 |
2205 |
4 |
2086 |
2142 |
2161 |
3 |
2039 |
2106 |
2138 |
2 |
2034 |
2088 |
2127 |
1 |
2028 |
2079 |
2109 |
Low Fire Ceramics (06-04 most common) |
01 |
1999 |
2046 |
2080 |
02 |
1972 |
2016 |
2052 |
03 |
1960 |
1987 |
2019 |
04 |
1915 |
1945 |
1971 |
05 |
1870 |
1888 |
1911 |
06 |
1798 |
1828 |
1855 |
07 |
1764 |
1789 |
1809 |
|
08 |
1692 |
1728 |
1753 |
|
09 |
1665 |
1688 |
1706 |
|
010 |
1636 |
1657 |
1679 |
Glass Firing |
011 |
1575 |
1607 |
1641 |
012 |
1549 |
1582 |
1620 |
013 |
1485 |
1539 |
1582 |
014 |
1395 |
1485 |
1540 |
015 |
1382 |
1456 |
1504 |
Decals 015 - 017 (015 - dishes) |
016 |
1368 |
1422 |
1465 |
|
017 |
1301 |
1360 |
1405 |
Overglaze / China Painting |
018 |
1267 |
1319 |
1353 |
019 |
1213 |
1252 |
1283 |
020 |
|
1159 |
1180 |
021 |
|
1112 |
1143 |
022 |
|
1087 |
1094 |
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Tester Cones
These cones tell you what your kiln is doing.
SSB - Shelf Sitter cones are
the most popular of the "tester"'
cones. They are Self Supporting cones that sit on your kiln shelves.
LRB - Also a Shelf Sitter cone, but is not self supporting. These are the older style, which some folks prefer. These cones sit in either a metal supporter, a bar with premade holes to insert the base in, or some people prefer to use a ball of clay to insert the base of the cone in. (We do have a few of these cones in stock. )
PLEASE KEEP IN MIND
THAT ALTHOUGH ALL THE
CONES LISTED BELOW
ARE AVAILABEL, WE MAINLY
KEEP THE MOST POPULAR
IN STOCK. IF WE DO NOT
HAVE THE ONE YOU NEED,
WE CAN ORDER IT. |
