- Never take risks with Kilns
- Never take risks with Clay
Unlike any other art form I’ve tried for any length of time pottery is the most unpredictable of them all. There are so many things that can go wrong when handbuilding anything that you soon find yourself having to improvise as you go. We always learn best from making mistakes, more so when something has proved a struggle and been difficult to achieve. My top tip of all is indeed to adapt to what is happening; and when frustrated leave it alone for however long you need to before deciding what to do next.
I seldom give up on a piece once I’ve built it. I have rarely thrown things away pre firing either. Even after firing a pot there are things you can do to avoid chucking it in the bin. For this blog though, I shall be focussed on how to end up with a pot that is reasonable assuming firings go well.
Clay does different things as you work with it. When it’s very wet it’s more difficult to control, when it’s dry it’s more prone to cracks, chips or flaking. For some creations it is occasionally desirable but most of the time you don’t want your clay to do that at all.
Slip, slurries and lumpy soups
A slip is made from water and clay and can be used in a technique called slip casting. It’s something I’ve never done but it’s a process whereby you use a mold into which you pour your slip and hey presto, once dry you have a pot. You can add colour to a slip such as an oxide or a stain but then the slip is generally used for decoration. You could use a coloured slip to help with repairs but generally people don’t.
For me a slip is distinct from a slurry because the clay particles are even distributed and suspended in the water. Slurries are similar but it just means the clay particles may not be either. The particles of clay tend to be larger in a slurry, meaning there is less water. It’s not a term used by potters as far as I am aware but it’s worth noting because with less water slurries are useful for repairs but most folk call it a slip.
To you can make up your slip/slurry so that it’s really quite a thick consistency but what you should avoid is a lumpy soup because as it dries the thin parts will crack and it is much more prone to chipping off and flaking too. When I first started pottery I had so many ideas that I often bodged repairs with a lumpy soup but it never turned out well after firing.
Clay used for throwing a pot is normally the dampest clay you will use and the first thing you do is add splashes of water to centre the clay on the wheel, then more water to ‘coil up’ and down to ensure all the clay has a perfectly even consistency. As I’m new to throwing I’ll cover thrown pots next year.
To begin any hand build you will need your clay to be damp and the first thing to do is pummel, bash and squeeze all air bubbles out of it so that it too is an even consistency. Air expands when heated, so even the tiniest air bubble can result in the clay exploding in the kiln. If you find one on the surface of rolled out clay you prick it with a knife then smooth over using a rolling pin.
On the next pages are ten more tricks and fixes for handbuilds.