Ceramics… How long does it take to make a ceramic piece? How hard is it to make? Those questions unfortunately offer a variety of solutions based on the skill of the potter and the complexity of the product. A ceramic artist must also contend with nature, chemistry, and sometimes just plain old luck. The nature of firing pottery in a kiln is unpredictable. The entire process is a chemical reaction and if anything is amiss pieces can blow up, glazes can run, and amazingly enough glazes can even change colors! With that said, as you can imagine there is no set answer to these questions but merely guidelines and estimates. However, I can give you an example that will give you a basic understanding of the process a ceramic piece goes through before it is finished.
Take for instance our mandala inspired circular weaving loom. The short answer… In ideal conditions with no distractions or mishaps, it takes 11 days to do this….
That timeframe however, as expressed above, is an estimate and largely determined by factors that are not in my control. For a detailed breakdown of what this creation process entails, see below! Fair warning, there is a LOT of info!!!
Creation Process in Detail
I have included both industry terms, which are bold, and simple explanations in hopes that everyone can understand this labor intensive process. If you have ANY questions, don’t hesitate to ask!!!
Clay Preparation – Total Time 20 min.
To begin any ceramic project, the clay must be wedged. This process is much like kneading dough. Begin with a lump of clay and push on it with your hands in a rocking motion until a “done” state is reached. The purpose of this action is to align clay particles and remove any air bubbles. Air in clay is almost a guaranteed disaster in the kiln, so this step can NOT be skipped! Here is a video that shows the Rams Head Spiral method of wedging clay for a visual.
Design Surface Creation – Total Time 1 day
Each loom begins with a slab of clay that is roughly 9 x 9 inches square. This square is simply a rolled out piece of clay that is trimmed to the desired size. You can hand roll the clay or as we do use a slab roller. This simple machine makes this step quick and painless!
The slab is then sandwiched between two ware boards, slabs of drywall or wood. This helps dry the clay to a soft leather hard state, stiff but still damp and not sticky. This usually takes a day in my current studio. Once soft leather hard, the clay is ready for decorations.
Decoration- Total Time 5 min.
The decorations on our ceramic looms are inspired by hand drawn mandalas. For the sake of production time, I have turned these drawings into a custom stamp. Each loom is stamped 4 times simply by eyeballing placement and hitting the stamp with a mallet. This helps evenly distribute the pattern into the clay surface. Note, not all our ceramic products incorporate stamps, this has simply made it so I can offer these looms at a reasonable price, saving you money!
Finalizing Design – Total Time 3.5 hours
Trimming and Clean up comes next. Each loom has a decorative edge and this must be cut out of the 9 inch square. I do this with a simple exacto blade by hand. As the cuts left by the blade once dried will be very sharp, I use a sponge, some water, and a small paintbrush to round off any corners and edges.
Once again, the looms are sandwiched between the ware boards and left to dry for about 3 hours. At this point, the loom is flipped over to the back so that the peg and anchor loop can be added along with my signature and number.
The leather hard loom is then transferred to a wired rack face up. This allows me to place a ware board on top to help ensure the loom dries flat. Any bending of the loom or slab up to this point is a potential disaster in the kiln as clay has a memory and when fired will return to that warped state.
Initial Drying – Total Time Average 8 Days
Now we wait. The loom must air dry SLOWLY until it is bone dry, all water between the clay particles has evaporated. This stage is dependent on the seasons and the resulting moisture content in the air. I must stress that I can NOT rush this process. If a loom is dried too quickly, cracks will develop or the loom will warp. Both scenarios will render the loom unusable, and I will have to start over. At this point, the looms have shrunk about 1/2 inch.
Initial Glaze Application – Total Time 1.5 hours
Once the loom is bone dry, it is ready to be painted with 3 layers of an underglaze color of the customer’s choice. The underglaze must dry between each applied layer for roughly 20 min. Underglaze is a colored slip, watered down clay, formulated to have a low shrinkage rate. After all the underglaze layers are dry, the looms are ready to be fired for the first time.
Initial Kiln Firing – Total Time 25 Hours
The initial firing of the kiln, furnace or oven used to fire pottery, is called a bisque fire. During this firing the following chemical stages are met:
- Complete drying occurs when the boiling point of water (100 degrees C, or 212 degrees F) is reached and all the steam is slowly released.
- Dehydration removes the chemically bonded water, water that is part of the molecular structure of the clay, at 350 degrees C (662 degrees F). The remaining water between the clay particles is removed at about 500 degrees C (932 degrees F).
- After dehydration, quartz inversion happens at 573 degrees C (1064 degrees F). This is where the quartz crystals rearrange themselves slightly.
- Burn off occurs at about 900 degrees C (1652 degrees F). All organic and inorganic materials are burnt off at this point.
- Finally partial vitrification is reached. Vitrification is the process of melting clay to its maturity point, in our case this occurs at cone 04, 1077 degrees C (1971 degrees F).
- Finally, the kiln and contents must cool down.
Final Glaze Application – Total Time 1.5 hours
The bisque fired looms are removed from the kiln once cooled and are now ready for their final glaze application and firing. There are 3 layers to this glazing process as well, dried for roughly 20 min. between coats.
Final Glaze Firing – Total Time 16 hours
The final vitrification will occur during this final firing along with the previously noted chemical stages above. Vitrification is the point at which the clay body has matured and all spaces between the refractory particles are filled with glass, making the ceramic product stable and strong. Our final firing is done to cone 05, 1043 degrees C (1911 degrees F)
Whew, told you this was a labor intense process! Just to sum it all up, yes all those times add up to just shy of 11 days to create one mandala inspired weaving loom. But don’t forget, this timeframe only works in ideal conditions with no distractions or mishaps. I’m currently shifting my current production patterns to negate any repercussions due to any issues that crop up along the way; but in the meantime, every kiln load that goes awry devastates me!