Making Clay Pots

On a whim I decided I wanted to make some pots.

It has proved to be a very interesting and valuable experiment that has taught me a great deal.

I did cheat in getting the clay. Instead of dredging some from a local river and then having to clean it and purify it I took the easy option and went and bought some from Hobbycraft instead.

Anyway.

The first dilemma was in adding temper to the clay. I was unsure of how much to add. I did some research but all advice said more or less the same thing – it depends on the clay and what you want the pot for. Some clay needs more temper than other clay. And pots that will be used for cooking will need more temper due to frequent temperature changes. The recommendation was to use temper that had hard edges so it ‘clung’ to the clay better. Some sands are made of smooth particles and may not be best to use. I used some modellers ballast.

So, how much temper to add? Between 20-30% seems like the best advice, but be warned you may need a little more or a little less, depending (see above). So I went with that kind of ratio. Once all mixed up I rolled the clay into a sausage about half-inch thick and coiled it up into a simple pinch pot.

Pot1

I used wet fingers and a wet ruler to smooth it out and shape it reasonably well. I didn’t spend too much time making it pretty since this first pot was going to be an experiment and could well crack and fall apart when it came to firing.

With the pot made I put it in the airing cupboard where the boiler is so it could dry overnight.

Next day I got a fire going, let it burn well to build up a good bed of coals, and then added the pot. You can see it here, beneath the coals.

Pot2

It was at this point that I realised I had no idea how long to fire it for! I seemed to recall from school, and from TV programmes like Time Team, that pots stay in the kiln for ‘hours’. So that’s what I went for. I kept the fire up for an hour, and then let it cool down in its own time; which meant it spent another hour and half in the hot embers. At the end of that time here’s what it looked like:

Pot3

All was looking good!

Pot4

Once it had cooled enough to pick up I could see that some of the clay around the edge had crumbled.

Pot5

I think this may have something to do with the amount of temper – too much can leave the pot brittle and crumbly. It was otherwise integral and firing had hardened the clay. 

I decided to break the pot up to inspect the fabric and make up of the pot and clay. When making it I had wondered  if the clay ‘sausages’ would knit together and become one, or if it would dry out and break along the sausage rolls. But no. The clay had fused and homogenised with no sign of how the pot had been made. The pot wasn’t as hard to break as I thought. I could easily snap it with my hands.

Here’s a close up of the clay so you can see the make up of the material. You can see the temper grains quite clearly.

Pot6

Although the pot didn’t come out 100% complete I had still learnt a lot from the experiment and think I know where and why things went wrong. So, in that respect, it was a success.

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