Pre-Heat has ended. (You can tell by placing a small
mirror near an open peephole.)
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To skip out of Cone-Fire Hold. Slow Cooling will begin.
(If the firing does not include Slow Cooling, Skip Seg-
ment will not end a Hold. Press
STOP
to end the firing.)
Skip Segment in Ramp-Hold
In Ramp-Hold, the firing will skip to the next segment
from either a ramp or hold of the current segment. (See
pages 14 - 18 for details on ramps, holds, and segments.)
Note:
Skip Segment does not skip from a ramp to a
hold. It skips to the new ramp.
Skip Segment Examples
For additional examples, see pages 17 - 18.
Cone-Fire
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In Cone-Fire you are firing to an 05 witness cone for the
first time. You select cone 04 with a 40 minute hold and
a slow cooling. You can see the witness cone through a
peephole. After 20 minutes in hold, the 05 witness cone
bends to maturity. Use Skip Segment to end the hold
and begin Slow Cooling.
Pointer:
Once you know how much hold time will
bend the witness cone, program that much hold for
the next firing.
Ramp-Hold
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Skipping to a Cooling Segment:
You have pro-
grammed 2167°F for a cone 5 glaze firing, followed by a
segment for slow cooling. Watching the witness cone
through the peephole, you notice that cone 5 is bending
at 2150°F. Use Skip Segment to end the firing segment
and begin the one for slow cooling.
Pointer:
Make a note of the temperature at which
the cone bent. Program that temperature for the
next firing. Adds comments like this to a firing log.
The ENTER/Start Key
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Press
ENTER
after each step in programming a firing.
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From
[IDLE]
press
ENTER
once to begin firing.
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Press
ENTER
to access an Option. See pages 19 - 26.
0 / The Options Key
See Chapter 6, page 19.
The Stop/Back Key
You can stop a firing at any time by pressing
STOP
. If
you inadvertently enter Ramp-Hold or Options, you do not
have to go through all the prompts to get back out. Press
STOP
to go to
[IDLE]
.
The
STOP/BACK
key works in Cone-Fire and
Ramp-Hold. It will take you back one step with each key
press.
Chapter 3
Cone-Fire
In this chapter you will learn to . . .
G
See witness cones at high temperatures
G
Program a Cone-Fire program in minutes
G
Pre-heat the ware so it doesn’t explode
G
Bend a cone by adding extra hold time
G
Cool slowly (called down fire) to alter glazes
Cone-Fire mode is based on pyrometric
cones. It is not designed for heat treating,
glass fusing and enameling. For these
firings, see “Ramp-Hold,” pages 14 - 18.
Use Ramp-Hold to fire ceramic pieces
that require a custom firing schedule,
such as some types of stoneware sculp-
ture or crystalline glaze.
Before using Cone-Fire mode, read all of
this chapter. Have your controller in
front of you so you can try out the keys as
you read. For more details on pyrometric
cones, please see your kiln manual.
Pyrometric Witness Cones
Question
A cone 5 firing was 7°F below the target
listed in your manual, and a cone 6 firing was 22°F
below the target. Is this typical and okay? Is the dig-
ital controller on my kiln operating normally even
though it did not achieve the controller tempera-
tures that were programmed at cone 5 and 6?
Answer
This is normal for Cone-Fire operation. If
the kiln fires slower than the normal rate, it will
shut off at a lower temperature. If the kiln fires
faster than a normal rate, it will shut off at a higher
temperature, sometimes by only a few degrees.
The Sentry controller
shuts off automatically with-
out cones. Nevertheless, ev-
ery ceramic firing should in-
clude at least one witness
cone (also called the shelf
cone). The witness cone is
placed inside the kiln. The
witness cone is the most accu-
rate measurement of heat
work in a ceramic firing.
10
Cone-Fire / Ramp-Hold
Do not leave your kiln unattended during operation.
Use self-supporting witness
cones on the shelf. They stand
upright without cone holders.
