Loading a biscuit, with last minute fixing of QR codes

One thing we realised from the bisque, is that the QR codes need to be accurate enough to give robust scanning results. This one wasn't working so well, so Christine made some adjustments before it went in the kiln.

Review of the plates so far

First big decorating night - Pittormie Farm plate

This post shows how the QR codes are printed onto the plate, using the laser cut foam stamps.

This is how the white clay slip is applied to the leather hard plate. The white clay is a ball clay from Devon. It is very difficult to find white clay in Scotland, though we are trying. The white clay is used to provide a contrast, so that we are able to draw through it with our designs.

Footring on a Pittormie thrown plate

This is the plate I have been most nervous of because the clay was very difficult to work, which is, of course, no reflection on the quality of the farm! I realise now I could have sieved the clay quite a bit more, and this would have made the proportion of clay higher in this mix. Still, I discovered that throwing is a superior way of making plates than press moulding, because it keeps the clay body compressed as it shapes it, while rolling clay stretches it out, breaking the microscopic joins that gives clay it's remarkable plastic quality.

Pittormie clay plate

Throwing a plate with Pittormie clay.

Pittormie plate using the new plate mould

This plate doesn't end well...

Clays from Fife!

Here are six of the clays we dug and collected from around Fife. It has been dried, slaked down to a creamy consistency, sieved, settled out, dried out and wedged. Now it is resting. From a potters point of view, in terms of workability, plasticity and strength, clay "improves" with ageing or souring. It is normally recommended that clay needs two weeks to sour, but potters in Chine and Japan used to keep clay in this plastic state to pass on to future generations. Clay also improves with being wedged (similar to kneading bread dough) or pugged (similar to passing through a sausage machine).

Plates to date

A selection of the plates to date. Pittormie, Clentrie (Puddledub), Pillars and Easter Kincaple (Seafield).

Test tile glaze firing

There was no difference between once fired tiles and twice fired tiles.

Test tiles fired

All the tiles survived and look good. The differences in colour is less marked now they have been fired. The clays could all be once fired with the glaze, but the structure of the plate (weak because it is flat) makes me wary of doing that, even though I have no problems doing so with the locally dug Easter Kincaple clay.

Making a plate from Pittormie clay

This clay was always going to be the most difficult to use.

Test tiles into kiln

The test tiles go in the kiln. You can see the lead glaze (brown) and the borax glaze (white). Below this shelf are unglazed tiles too.

Dried test tiles

The variety of the unfired colours of these clays is lovely.

Making test tiles

Test tiles were made of each clay. I made a stamp which had a 10cm raised line on it, so we could check the shrinkage of the clay after drying and firing. One set of tiles were to be raw glazed (once fired), and another sample biscuit fired, glazed and glaze fired. Two glazes were being tested, a borax glaze and a lead glaze.

Wedging Pittormie (1) clay

This clay is difficult, sticky and very short.

Clay drying

Clay drying and settling

Sieving and drying out clay

Slaking and drying

This clay is now dry and ready...