Digital controllers monitor and control glass kiln heating and cooling processes during the glass fusing cycle.
This type of controller when fitted to a glass fusing kiln will allow the artist great flexibly when setting firing schedules.
Unlike infinite control warm glass kilns you do not have to continually monitor the total fusing process.
Kilns fitted with a digital controller have very few parts and may only contain six major components that control the total fusing kiln operation.
Knowing these parts simplifies your knowledge of how a digital kiln works.
1. Fuse: Helps prevent the kiln from power surges.
2.Transformer: Reduces the incoming mains voltage down to 24volts AC to operate the digital controller.
3. Digital Controller: Programs are entered, stored, controls temperature and rate, and sends instructions to the relay.
4.Thermocouple: Located in the kiln firing chamber. When heated it sends a small voltage to the controller which is read as a temperature.
5. Relay Switch: The controller will send a 12 volt signal to the relay which will cause the contacts to close and send mains voltage to the heating elements.
When the contacts open the voltage is cut until the next signal.
6. Heating Elements: The elements can be located in the sides, the top, or in the top and sides depending on the glass kiln design.
These controllers make firing fusing projects very easy.
They can be programmed to heat, hold the temperature and control the rate of cooling for annealing then turn the kiln off automatically.
Subject to the maker and model, controllers may hold a only few programs up to the professional units holding up to 20 segments and advanced options.
For the home jewelry maker interested in making handmade glass jewelry there is a good range of kilns fitted with digital controllers from 6-inch square firing chambers upwards.
You are able to set the temperature rate increase up to a given temperature and the length of time you wish the kiln to remain at that temperature.
This is known as a segment.
Subject to your controller you will be able to program a number of segments to arrive at your fusing temperature.
Glass is usually taken through a number of temperatures before it fuses. This is to ensure it heats evenly and is not subjected to thermal shock due to a sudden increase in temperature.
Cooling segments are also programmed to ensure the glass is annealed properly to ensure cracking of the fused piece does not occur.
Setting programs is very straightforward and the information is easy to enter.
Information is entered by pressing buttons located on the front of the controller. All details can be seen in the window.
Once the program is loaded you start the kiln and the program will be run automatically.
Size Of Kiln: You need to decide what type of fusing work you want to do.
Analyze the type of glass art you interested in. If you wish to make dishes and vases then you may need a large kiln.
If you are only interested in making jewelry then a 6 to 8 inch kiln may well be big enough.
Many of these glass kilns only have side elements which are fine for small fused glass jewelry pieces.
They may not be suitable for firing small thick plates as the heat tends to hit the side of the object rather then the middle of the glass.
A top element kiln will evenly heat the glass and will produce good results for most fusing projects.
Kilns with top and side elements tend to be larger and more expensive.
Power Needs: The larger the kiln the greater the power needed to run the kiln.
Most small kilns will plug into the normal household 120 volt 13 amp outlet.
Large 8 sided and square kilns may operate on 240 volts and require a special outlet and wiring fitted by a licensed electrician.
Always check with the manufacturer and an electrician before purchase to ensure that the kiln is suitable.
The following video gives a demonstration of digital kiln programming.