Read "Pyrometric Cone" chart is not that difficult
Pottery Clay has already introduced a temperature measuring device known as 'Pyrometric Cones' to everyone before. This time, we will teach you how to read this device. Let me tell you that it's not difficult. Let's see.
How to take a pyrometric cone reading for measuring temperature starts by setting the curve to match the position of the number on the watch: 1, 2, 3, 4, 5, 6. When start using it, you need to notice where the tip of the buoy is curved downward by assuming the position of 3 o'clock to be the correct temperature of that buoy type. The buoy with different code numbers means different buoy ingredients and different heat resistance. The type of buoy is assigned to the number of SK (Seger Kegel)
However, when measuring the temperature with a cone, one must be careful about the rate of heating inside the kiln, the atmosphere inside the kiln, gas velocity, and temperature of the kiln wall because all of these affect the discrepancy on the weakness of the cones.07’ The temperature of the bottom of the kiln should be slightly hotter than the top and should place a non-flowing enameled container in that area
Another thing that must be strictly adhered is you should not look at the cone with the naked eye. You should always wear glasses or a mask because when firing at high temperatures the fire in the kiln will be so bright and yellow and almost white that it can cause blurry vision or be dangerous to the eyes. If such a case occurs, you can blow air into the firebox to read the value of the cone more clearly. Always carefully clean the firebox before loading the container in the kiln. This prevents the remains of ash from being blown onto the container while blowing to read the cone.
Using cones will help to keep the sintering temperature accurate. In each firing, the base should be kept and examined for bending, and recorded especially the sintering is successful and has achieved the desired glaze color so that the kiln can be turned off while the base bends in the same way for the next firing.