How clay works

So to be successful at making an item out of clay your going to need to know it's weaknesses and strengths, to avoid smashing, smooching or generally crumbling.

WET CLAY

Straight out of the bag clay is wet and sometimes sticky. The water content greatly effects the structure of clay, at the first the water will have been effected by gravity, sat in the bag. Wedging the clay helps to redistribute the water and clay particles and this helps prevent areas of weakness which will cause cracking in the kiln.

You can watch videos on you tube demonstrating wedging techniques, remember though we are only using a small amount so don't Wedge clay unless you're planning on using it straight away. In my you tube video I skip this stage as I dont find it so essential with smaller projects, the rolling gets the job done, but its an important skill to learn and I shouldn’t teach you my bad habits now should I?

DRYING CLAY

The clay will be less sticky now. If you were to leave a piece out, eg the size of a biscuit it would start to dry and firm up, it goes from being soft like pastry to stiff like card (called LEATHER HARD) and the pale and brittle (called BONE DRY) see paler plate in pic.

The time it takes for each clay goes through the drying process depends on the clay and room temperature, it's best to make a test piece and observe the timings. a good guide to remember would be……..

FORM- wet clay can be changed in shape, but don't try to alter it after it's started to firm, as it will crack.

FINESSE- leather hard clay can be carved, smoothed with a slightly damp sponge, and parts joined together with slip (runny clay)

FINGERS OFF!- bone dry clay is brittle and easily shattered, touch it as little as possible! Handles will not hold the weight of the cup and are easily knocked off, do not add anything damp as at this stage nothing can be changed, we need them completely dry to fire them

SLIP- this is a runny clay that looks like a super thick chocolate milkshake. If you made a test piece to observe the drying stages, you can smash it up and add it to a little water in a jam jar and this will be perfect for joining handles and bases, we always use slip made from the same clay as the main body.

We call these stages Greenware, as the clay is raw and unfired.