Using Small "Test" Kilns as Only Kiln

[PSC]

I have a small test 11x11 kiln, i think it is a skutt. It is not computer controlled.  I have noticed it fires a little higher than the larger computer controlled kiln at the place i teach at. High enough difference that satin matts tend to be semi gloss in the test kiln.

[neilestrick]

9 hours ago, PSC said:

I have a small test 11x11 kiln, i think it is a skutt. It is not computer controlled.  I have noticed it fires a little higher than the larger computer controlled kiln at the place i teach at. High enough difference that satin matts tend to be semi gloss in the test kiln.

The difference may be due to cooling times, not firing temp. Little kilns cool a lot faster, so there's no time for crystals to grow. Add in a cooling cycle of 175/hr from peak temp down to 1500F and see what happens.

[bny]

I have two of the Paragon Caldera kilns with Orton digital controllers.

They will run on a standard household circuit.  It would be better to have a dedicated circuit installed with the most heaviest gauge copper wiring allowed by code.  I tried running mine on an outdoor patio outlet distant from the panel, but this did not work well.   Any energy that is not being dissipated inside the kiln, is being dissipated by the house wiring, and who knows how hot that is getting.  I now run it on a garage outlet, which is the closest outlet to the panel.  It will not run well on even the heaviest gauge extension cord; it must be plugged directly into the outlet.

If you are having a new circuit installed, it might as well be 220V, which gives you a wider choice of kilns for cone 10.

I am partially satisfied with these Paragon units with one notable exception: mine will make 2300 F only for around 6 firings.  Both degraded to be reluctant to make even 2200 F in any reasonable amount of time.  I replaced the elements in one, and the replacement elements also made only around 6 firings at 2300 F.  The time to reach 2300 F increases with each firing.

My work is technical (small wares dry-pressed from powder).  I do not use a cone schedule, and instead typically run the kiln at full rate to the target temperature, with a designated hold time at that temperature.  My most pleasing and technically best results come from a feldspar+kaolin composition that requires 2300 F. 

I have had to compromise the composition by removing kaolin, adding an organic or sodium silicate binder to replace the binding function of the kaolin, then adding one or another type of frit to get the firing temperature down to 1900-2150 F.  This does not give a pure nearly translucent white result, but it is good enough to investigate most other aspects of the process.  This without having to deal with sharp fragments of brittle used elements, and abuse of the delicate firebrick.  Replacing elements in the close quarters of the Caldera, is not a pleasant process.

It is possible that the Caldera would have a longer element life at higher temperatures, if it were on a lower resistance dedicated circuit.