Our next firing is Saturday 7th October 7.45am start
Loading Thursday 5th October 2pm, unloading Monday 9th 2.00pm
Please have your work on the gas firing shelves by 5pm, Wednesday 4th October
The last kiln firing, August 19th, ran very smoothly with a full gas cylinder and Luci in control. It was another full pack with just a few pieces from Rod and me missing out (again). Lots of glaze samples in the firing prepared by the 'Cooking with Gas' team and we will use the time between monitoring the next firing to set out the display of these. This resource will give everyone an idea about each of the gas firing glazes and how they respond and are modified over most of the clays stocked by the club.
The firing results were very good with lots of interesting work, largely blemish free. That comes from taking care with margins at footrings and an increasing use of setters. It was pleasing to have some classwork in the firing.
Just one negative point from the firing and that relates to the new Deco buff clay. Faults, variously described as shelling, peeling or shivering, occur when the clay body shrinkage is more than the glaze can accommodate and so flakes off, particularly on edges and rims. It is the opposite fault to crazing. In extreme cases this can result in parts of the body fracturing, the glaze being stronger than the body, and my experience is that this result can be delayed over a few weeks.
This may be happening with all or just a few of the gas firing glazes, you will need to monitor your results from your favourite glazes if you are using this clay and feed faults back to the glaze team. We already have these bad results from Nick. My suggestion is that this clay is not put forward for cone 10 firings.
So we can highlight the need to understand your clay properties from the manufacturer/supplier. This Deco buff clay has a firing range up to 1280 °C. By our cones we are aiming to fire to cone 10- 1310 °C. It seems then this clay has its structure changed enough during this last 30 °C of our firings so that the clay and the glaze no longer fit. We will hear more about results with this clay if members continue to use it in the gas kiln.
This October firing should clear work for the Kapiti Art Trail, which is at the beginning of November. I am expecting another firing early December for your Christmas gifts and for the Festival of Pots at the end of January. Work on the shelves will be monitored for demand for an additional firing over the November - January period but no guarantees about that at this stage.