Entering a Cone-Fire
Program
Firing Speed [SPD]
When you select Medium speed in a Cone-Fire pro-
gram, the kiln uses the standard firing schedules listed on
pages 30-31. When you select Fast, the standard schedules
fire 20% faster. On Slow, they fire 20% slower.
Pointer:
The Medium speed appears in the display
as
[STD]
(Standard).
Note:
The final segment heating rate will not
change. It will always be 108°F/60°C per hour. Slow
and Fast speeds affect only the earlier ramp seg-
ments of the Cone-Fire schedules on pages 30-31.
Hold at Cone Temperature [HOLD]
Cone-Fire Hold heat-soaks the ware at the cone temper-
ature. Without Hold, the kiln shuts off after it reaches the
cone temperature or Slow Cooling begins. Hold maintains
the cone temperature for the length of time you specify.
Hold is not needed in every firing. Experience will help
you decide when to use Hold. Some of the reasons you
might consider using it:
I
To even out the temperature throughout the kiln.
I
To allow heat to penetrate more completely into the
clay. (Rapid firing is like cooking: the turkey will be
done on the outside but not on the inside.)
I
To help glaze absorb china paint.
I
To heal glaze defects such as bubbles.
CAUTION:
Too much hold time can overfire your
ware and burn out colors. Be sure to experiment
with hold before firing a full load of ware with it.
One way to add hold time without over-firing is to fire to
one cone cooler than needed. Then add enough hold time
to bend the next hotter cone. Hold time needed to bend the
next cone will vary. As a rule of thumb, 20 minutes of hold =
one cone of heat work.
Example: to fire to cone 05, program Cone-Fire for 06
and add 20 minutes of hold time.
If your kiln has a peephole, watch the pyrometric witness
cones during firing. Press
Stop/Start
when the correct wit-
ness cone bends. Note how much Hold time was needed.
Program that much Hold time the next time you fire the
same type of ware.
Note:
During Hold, the display temperature will
alternate with time left in Hold. To figure hold
time for the next firing, subtract time left in Hold
from the total hold time entered.
Sentry Xpress 5 Cone-Fire / Ramp-Hold
10
Do not leave your kiln unattended during operation.
Cone-Fire Programming
Instructions
Lock, Slow Cooling, and Delay can each be turned on
or off as programming steps. Ignore the steps below that
you have deactivated. See LOCK, page 21; COOL, page
17; and DELA, page 17.
1
From
[IDLE]
, press
Start/Stop
(left button).
2
Using the
Up Arrow
key (not the
Down Ar-
row
), skip past
[USER]
and select
[CONE]
.
Then press
Start/Stop
.
3
The last pyrometric cone you fired will appear.
Use the arrow keys to change the cone number.
Then press
Start/Stop
.
4
If the program is locked,
[UNLO]
(Unlock) will
appear alternating with
[0000]
. If you want to
change the program, enter your passcode. Oth-
erwise press
Start/Stop
, which will take you to
Step 9.
5
[SPD]
alternating with
[SLOW]
,
[STD]
(stan-
dard) or
[FAST]
will appear. Use the arrow keys
to change speed. Then press
Start/Stop
.
6
[HOLD]
and the hold time from the last firing
will appear. (Example: 1 hour and 10 minutes =
01.10) Use the arrow keys to change the hold
time. Then press
Start/Stop
.
7
[COOL]
will appear. Enter a slow cooling rate
as degrees per hour. (180°F/82°C is the maxi-
mum cooling rate. Enter 0 to turn Slow Cooling
off.) Then press
Start/Stop
.
8
[LOCK]
alternating with
[0000]
will appear.
Enter your passcode to lock the program, or
press
Start/Stop
to leave it unlocked.
9
[STRT]
will appear. Press
Start/Stop
.
[DELA]
will appear. Set a delay time. If you don’t need to
delay the firing, leave the time at
[00.00]
. Then
press
Start/Stop
.
[-ON-]
will appear, the Run
indicator light will begin blinking, and the kiln
will begin firing. If Delay was programmed,
[DELA]
will appear, then time remaining until
start.
To stop a firing before completion, press
Start/Stop
.
[ABRT]
(abort), the firing time, final firing temperature,
and current temperature will appear.
When the kiln fires to completion, it will beep for 30
seconds.
[CPLT]
(fired to completion), the firing time,
final firing temperature, and current temperature will
appear.
To return to
[IDLE]
, press
Start/Stop
.
To fire the same program again, see “Program Re-
view & Repeat Firing,” page 5.
