Choosing an appropriate kiln is dependent on your budget, space and the electricity
available for your work space. A good start is a small kiln with a 6 – 9 inch square
interior space, which uses 110 volts and no more than 15 amps (normal household
current) and uses a standard three prong plug.  A small kiln can be placed almost
anywhere that is not accessible to pets or small children and may be easily stored
when not in use.

Even small kilns should at a minimum be purchased with a rotary dial “infinite
switch” that permits rough manual control of the temperature through low medium
and high ranges. The kiln will also need at least a dial type pyrometer which is a
gauge that loosely displays the current temperature inside the kiln through a
connected thermocouple probe that passes through the wall of the kiln.

A nine inch kiln uses an eight inch kiln shelf giving you 64 square inches of space to
fill with your dichroic glass items.  A six inch kiln uses a five inch shelf so you get
25 square inches of fusing space.  Unless weight or financial constraints require that
you buy the smaller kiln, you will find the 9 inch kilns extra capacity a real plus.

Even if you later get a larger kiln, the small kiln is always useful for small items and
firings and for making pre-fused elements to use in other fusing work.  My small 9
inch kiln has been in daily use for the past ten years and it costs less than 25 cents to
fire it for an hour which is longer than most fuse cycles.  Large kilns require 220
volts, higher currents, cost considerably more and take much longer to fire.  They
are also less suitable for small pieces, because you will want to “fill” a kiln shelf
before firing and that will take many, many more pieces. When you fire smaller
batches you have the opportunity to make changes and adjustments between firings.

A digital set point temperature controller is much more accurate than the infinite
switch / pyrometer method and will maintain any preset temperature with great
precision. This makes possible much more predictable and repeatable results and is a
worthwhile investment even when starting out which will help to avoid much
frustration. It is easy with a small kiln to over-fire your glass in just a couple of
minutes.

Computer / multi-ramping controllers permit the user to program multiple
temperature and rate profiles for complex firing sequences. These can operate
without operator intervention, permitting complete fusing cycles to be carried out
automatically. However, during the firing cycles it is still an important safety
measure to be present in the vicinity of the kiln. For repetitive and complex work
these controllers are excellent, albeit expensive. Computer controllers are truly
necessary for larger kilns where larger and thicker pieces may be produced that
require complex firings with extended and exacting annealing cycles. 

Check out the warranty on the kiln that you buying as well.   You want one with at
least a one year warranty on parts.   Most kilns work very well for a long time, but it
is comforting to know that there are people to help you out if there are problems.