Choosing a Kiln

Over 1500 quality clay and ceramic products for hobbyists, teachers, and potters.

HOW TO CHOOSE AN ELECTRIC KILN

SIZE YOUR NEW KILN TO FIT YOUR WORK

Think about size in terms of the amount of work you are going to produce and the largest piece you need to put in the kiln. Assume you will get one firing per day at the most. The larger kilns cost less to fire per piece if fully loaded.

NORMAL VOLTAGE IN THE USA

Most kilns are available in either 240 or 208 volts and in either single or three phase. Most household voltage in the United States is 240 volts single phase. Typically only schools, institutions and factories have 208 volts or three phase.

HOW DO YOU KNOW?
Do not assume you know your voltage. Check with an electrician or your electric utility company! There can be a variety of voltages in one building.

ENERGY SAVINGS?
There is no energy savings for the various voltages or phases; choosing is purely a matter of what you have available.

WHAT HAPPENS IF YOU ORDER THE WRONG VOLTAGE?
Be careful because if you order the wrong voltage the kiln will not operate properly (for instance a 240 volt kiln will loose 25% of its power when operated on 208 volts). You will have to change elements at considerable expense.

NON-US VOLTAGE
Voltage outside the United States is typically 220 single phase or 380 three phase.

.
CONSIDER THE COST OF MAINTENANCE

How hard are you going to use the kiln? If you are only going to use your kiln once a month for hobby use then perhaps you can get away with a cheaper kiln. If you are a school, an institution, a factory or a serious artist who depends on your kiln for a living, then you should seriously invest in the most trouble-free kiln you can buy. Although the exact cost of maintenance savings is hard to calculate, it can add up to major savings in time and money. Think about this when you compare kilns.
.

AUTOMATIC VS MANUAL

RELIABILITY, CONVENIENCE, ARTISTIC FREEDOM
The newer program controls are quite reliable. They automate the firing process providing great flexibility and a new level of control which can open up new creative avenues. They are particularly helpful for busy teachers who don't have the time to baby-sit a kiln.

.WHY DO PEOPLE BUY MANUAL KILNS?
Manual kilns are slightly less expensive and rely on pyrometric cones and manual turn up of kiln input switches to profile the firing cycle. Some people feel more comfortable with "hands on" control and some people don't want another programmable device in their lives. Manual controls are easier to understand (although not easier to use) and are not subject to electrical noise. That being said, manual controls require maintenance to help prevent problems in firing. Skutt kilns can easily be upgraded later from manual to computer. Also, many kilns mounted with computers don't have the safety devices that manual kilns have.

THERMOCOUPLES
Manual kilns use no thermocouples (which are a consumable item).
.

.. SINGLE ZONE VS MULTI-ZONE

THE PROBLEM WITH GRADED ELEMENTS
Many kilns on the market have all elements controlled as one zone. Typically in such designs the elements are graded in power output from top to bottom (to adjust for temperature uniformity due to greater heat losses at the top and bottom). There are two problems with this. First, there is no way to adjust for varying load conditions. Second, as the elements age and change in power output (and they will do that at varying rates because of their different designs) the built in adjustment will change. The only way for you to fix this is to change all the elements at one time - an expensive proposition.

TOP-LOADING V/S FRONT-LOADING

Many people prefer front-loading kilns for ease of loading and better insulation. These are more expensive than top-loading kilns. The reason is that they take much more time to build and require more expensive materials (i.e. there is a heavy welded case). Beware of “inexpensive” front-loaders that are cheaply made. Front-loading kilns are also more expensive and difficult to repair.

SECTIONAL VS SINGLE PIECE

MOVING AND REPAIRING A SECTIONAL KILN IS EASY
Top-loading electric kilns are either sectional or one-piece construction. Typically sectional kilns have 9" high sections that sit on top of each other. Sectional kilns are easy to move (often one person can do the job) and easy to repair. Kilns made with a single piece case are usually less expensive but have obvious disadvantages. They are very difficult to move and repair (you may have to disassemble the whole kiln).

BRICK AND INSULATION

ENERGY SAVINGS
Top-loading kilns typically come with either 2-1/2" or 3" thick insulation. You will save energy with 3" brick (and have a stronger kiln). 3" brick will also slow the cooling of the kiln (which is often desirable for pottery). However, total energy saved is minimal in low-fire applications. This is because 3" brick takes more energy to heat itself up. We definitely recommend 3" brick for high fire applications (over cone 1 - 2000F).

ELEMENTS

Almost all electric kilns use alloy elements made of Kanthal A-1 or the equivalent.

APM ELEMENTS
Another rather expensive upgrade, APM alloy elements, is available at more than 3 times the cost of heavy duty elements. We don't recommend APM elements except for the most extreme circumstances (like everyday firing at Cone 10).

L&L'S UNIQUE & EXCLUSIVE HARD CERAMIC ELEMENT HOLDERS
L&L's hard ceramic element holders embedded in the firebrick solve this problem. You can actually hit the holders repeatedly and cause very little if any damage to the firebrick interior of the kiln.

TEMPERATURE RATING

DO YOU NEED A CONE 10 KILN?
Electric kilns range in maximum temperature usually up to Cone 10. This is mostly a function of kiln power available. Can the kilns reach Cone 10? Even if you are not going to use the kiln to Cone 10 you will still benefit from the higher power available. As elements age the kiln firing will slow down. If you start with a more powerful kiln you will get more life out of your elements.

WHY VENT A KILN?
A powered kiln vent is a good idea. It eliminates the need to crack the kiln lid to manually vent the kiln. Carbon, carbon monoxide, sulfur, water vapor and other fumes are generated from firing clay and glazes. A powered vent removes these fumes from your kiln and kiln room. The fumes can damage the kiln or your ware and can be hazardous (for instance carbon monoxide).
WHY USE A DOWNDRAFT VENT?
A downdraft vent that attaches directly to the kiln is recommended because it is so effective, promotes kiln uniformity, and improves glaze colors.

GENERAL VENTING
A good room vent or at least an open window is also recommended in conjunction with the kiln vent.