This is the first in a series of posts where I will be sharing a few things that you may find interesting about the pot making process. It is this kind of knowledge that fuelled my deep interest in ceramics quite a few years ago now.
One of the questions I get asked when making a commission for someone is how long it will take to make the pot? 'How long is a piece of string?' is not the best answer to give to a customer when you are running a small business. However, there are a number factors worth considering.
The biggest factor is which potter you ask. Their set up and workflow is a big determinant of the speed in which they could make your pot. I work with a number of different clays - some almost white as well as browns, reds and black. I also make pots using a range of techniques. I throw round pots on a wheel and I use clay coils or clay slabs for other shapes. I have a workflow where I only work in phases or making cycles. A making cycle will usually be one clay with one technique (wheel, coil or slab). This is for a number of reasons - I use a range of tools (I have hundreds of pottery tools) and I can't mix the clays up by using tools on more than one clay at once or through contaminating my work area. I also develop a rhythm when constructing pots using a certain method - absorbing myself in 'the flow' as Mihály Csíkszentmihályi describes it (look it up - very interesting!) So, in a given week I will be using one clay and one method of construction - you can begin to see how a request to make a 'rectangle in black clay' for example may be a few weeks before I even start.
Once made from raw clay, the pot can take a week or two to get to the point where it is 'finished'. By finished, I mean ready for drying. My round pots are thrown, allowed to dry for between 1-5 days depending on time of year (and therefore humidity levels), then put back on the wheel and trimmed. It is at the trimming stage where refinements are added, feet are cut and details added to the finish. Round pots can then take a few more days to become 'bone dry'. Once bone dry, a pot is ready for its first firing. (I'll come back to this later.)
Now coil built bots and slab pots are a different beast. They too need an initial build phase which can take a few days - refinements are completed as the pot slowly dries and the clay becomes workable in different ways. However, unlike my round pots, they are not made from a single piece of clay but rather coils and slabs that are then joined together. The drying phase needs to be slower to avoid warping and cracking. Some of my pots can take weeks (or even months!) to become fully bone dry. They are wrapped in plastic and are checked, unwrapped and rewrapped regularly to slow the drying process down.
(a large coil-built oval pot at two stages of its initial construction)
Finally, when the pots are bone dry, they can be given their first firing which is known as the bisque (or biscuit) firing. this turns the brittle and fragile 'greenware' clay into a hard (yet porous) form. Now, some potters will talk of temperature but I prefer to talk of the heat work instead. Temperature is secondary; it is the heat of a firing that is the important part. Not to bore you with chemistry but it is the heat of a firing that creates the magic rather than the temperature. We measure heat through something called cones (I'll maybe come back to this another day) and it involves a combination of heat and time.
The first firing is at lower heat than the second firing and it serves an important purpose. It gets the pot ready for glazing. The pot can now be handled more firmly and should have the correct degree of porosity for the glaze process. (I have another blog post on this to come...) Once the glazing is complete and the glaze is dry, the pots can be fired for a second time to a much higher temperature (or heat). It is this second firing which is so important to owners of bonsai - this is the point at which the clay becomes stoneware. However, I am going to say this now (and explain it more fully in the future) - stoneware is not to do with the temperature the clay is fired to, it is the heat and it is purely dependent on the type of clay being used. Stoneware is vitrified clay that is no longer porous (a discussion on porosity levels in stoneware is not for this post).
The bisque firing can take about 18 hours from start to finish and the glaze firing can take at least 24 hours - depending on the firing cycle (different glazes need different firing cycles - again an article for another day).
However, the size of kiln is also important - a potter will usually only fire a full kiln. This is for two reasons. the first one is cost - it makes sense economically for an expensive gas or electric (or even wood!) firing to fill the kiln before you fire it up. Secondly, you get a better heat distribution when the kiln is full - a half full kiln will fire completely differently. This can add to the time it takes to get your finished pot, as a potter will need to fill their kiln before firing.
So, how long will it take to make your pot? It depends .....
(If you have any questions about the above, please pots a comment below and I'll be more than happy to answer!)
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