Answer: Because a kiln is a thermally insulated chamber that reaches over 2,000 degrees Fahrenheit and you need this kind of heat to properly bake clay.
Surely you have heard about pottery making. If you aren’t familiar with it, then you have probably seen one as a decoration in a mall, a restaurant, museum, and even your house without even realizing it. One of the earliest art forms dated was Pottery making.
This can produce all kinds of ceramic pieces you want or desire. This is without a doubt one of the most well-known art forms up to date. It is not only because it produces beautiful art ceramic pieces, but it can also be a way to reduce stress because it is incredibly therapeutic for most people.
You are given a chance to produce art and express yourself from a creative standpoint, so having many people finding pottery making a much-needed hobby is not a baffling idea at all. Pottery indulges you to create beautiful art pieces freely without having to have the skills of Picasso.
You only have to join a few pottery classes to help you get the general idea you need to understand how to do pottery making at the comfort of your own home. It is a great feeling to produce useful pieces yourself. Eventually, if you keep on practicing, your work will get better and better.
However, pottery making is not only about creating the piece itself. It is also extremely important to know how to complete and finish your ceramic piece. If you are planning to do pottery making as a hobby, it is a good choice to invest in a kiln.
Why You Should Invest In A Kiln For Pottery
There are reasons why people do not invest in kiln though. Since kilns are quite expensive, it is not a good idea to purchase them unless you are planning to make potteries constantly. It is not suggested to buy a kiln if you do not have the time to dedicate to making this a hobby, It is also suggested that you weigh your options if having a kiln is feasible for you.
Kilns often take up a lot of space in your area, so keep that in mind. Firing without using a kiln is usually what tribal people do since they can contain the clay at a higher heat. They also prefer a bonfire-type setting and it is also a relatively easier way to contain.
Firing without a kiln does create beautiful ceramic products as well, however, there are too many problems that you may encounter when you are not careful. So, if you are planning to turn pottery making into a hobby, here is why you should invest in a kiln instead.
A kiln is basically an oven used for firing, drying, baking, burning, hardening or cause chemical changes that produce the right temperature needed to complete the ceramic.
Upgrading To A Brick Kiln Is A Big Deal
The brick kiln was a major upgrade from the primitive process of sun-drying the product since it provides stronger brick. Nowadays, the modern kilns we have are used to finish the ceramics. They are either lined with firebricks or made entirely of heat-resisting alloys.
Kilns were specifically invented to contain the heat to reach the needed temperature with lesser fuel needed. When making pottery, there are three main factors that can affect the overall product, workability, color, and temperature.
Knowing this, it is essential to have a kiln that can provide you with the exact temperature you need when firing. The right temperature can remove the water molecules in the clay and converts the clay molecules to molecules that do not break down in the water.
What Happens When You Bake Clay In A Kiln?
Firing a ceramic in a controlled place like a kiln requires awareness of kiln contents, the process, and the objective. It is important to know how flexible and sensitive wares are when fired in a kiln. Think about it as the process of making metamorphic rocks.
The wares are changed in form just like how metamorphic rocks are formed through the forces of heat and pressure. There is also the glazing happening at the same time.
The kiln contains bodies and glazes which are usually one of the big things we focus on when firing. Both physical and chemical changes are happening inside a kiln during firing.
The physical changes may cause us agitations and headaches wondering if the ceramics you are making is alright, but the magic happening in the chemical changes is absolutely fascinating and makes the whole process worthwhile.
The Stages Of Firing That Takes Place In The Kiln
There are several stages of firing that is happening inside the kiln. First is the final drying which basically means that the ware has to be fully dry to prepare for the bisque or prefiring of the ware to make it water resistant or preparing for single fire.
Whatever process you do, it is essential to dry the ware thoroughly, understand the air flow inside the kiln, the venting ability of the clay, and density. This will allow you to adjust any matters to ensure success. Next, the ceramic undergoes changes after the bisque or single fire is done.
Shrinkage will not occur during this time but the ware is extremely fragile since it lacks particle mechanisms that helps the bond.
During this stage, proper airflow is needed for single fire ware so the steam can escape and prevent any damage in the existing bond between the glazed body. Next is the quartz inversion and conversion.
After this, burnout occurs. It is important to have proper oxidation and enough time to avoid the black coring and any expansion and strength problems.
Next is sintering, where chemical bonding is developed. Decompostion then happens where the oxide is rebuilt undertaken by the fire inside the kiln. Then, some people use reduction to get the rich iron brown or earthtoned colors.
It is then vitrified, that is developed in the body of the clay during firing. After all of this is done. the ware is cooled completely. It is an important process where the actual glass-building is formed. To put it simply, as the ware cools down, the glaze solidifies and an element of crystal is formed.
Yes, the firing process is more intricate and complex than most people think. Rest assured, you can just fire a kiln and you don’t have to know all of this just like how you can bake a cake just by setting the oven timer and wait for it to be finished.
Does kiln-Baked Clay Decompose With Time?
It is important to note that when clay is fired, the silica and other elements will melt and change. This is not just dried clay, it is more classified as stone. Clay when fired is chemically decomposed into igneous rocks. The firing process turns the clay to a stone-like state.
So naturally, this will weather and decompose like stone. It basically means that this will change very slowly following a lengthy geologic procedure. The oldest fired-clay we have found is about 25,000 to 29,000 years old.
The only change that happened during that time period was caused by breaking and not decomposing. The object was identified to be very low-fired, so if they had the knowledge to create kilns and make high fired pottery, many wares would have lasted.
Why Can’t I Just Use My Oven To Fire My Clay?
Remember that you can’t fire your clay in your oven. However, you can bake it instead. If you don’t want to invest in a kiln, you can actually start by making your pottery in your oven.
When you decide to bake your pottery in the oven, you can learn the basics without having to think about the technicalities of firing a kiln. If you wish to teach your children, this is a great way to introduce them to pottery making.
When using the oven, you should be using beginner clay, so there is room for errors and you don’t have to be too careful with your work, and again, great for teaching children.
However, making your clay in the oven has its limitations. You can’t get your oven very hot compared to a kiln. There won’t be any chemical changes happening like when you are using a kiln. You will not get that “glassy” look as much as a klin does. It is also dangerous since it can possibly combust and explode when you push it too far. If you are also not careful, it can also melt the clay or crack it.
If this has convinced you to purchase and invest on a kiln. There are some things you must consider to get the best kiln that suits your preference and needs. Purchasing a kiln is a major spending so it is important to take steps that will ensure you will be satisfied with your purchase in the long run.
So, before you buy a kiln, think about what are the specific things you need from a kiln. Weigh the options on what energy sources that are available to your studio and match it to your kiln. Check the insulations the kiln you are about to purchase have. Not all kilns have the same ability to hold heat.
Also consider the space available in your studio and the size of the kiln, especially when you are planning to place your kiln indoors. Make sure to check the regulations and the restrictions when operating a kiln. Lastly, make sure to understand how your kiln operates.
Read the manual provided and make sure that you are able to work with the kiln efficiently and safely. Whatever equipment you want to use, whether it may be using a kiln, an oven or do it outdoors instead through pit fires, it is important to learn the know hows on how each of these procedures operate to get the best result on your ceramic art works.