The Naked Raku Process
Most of my pots are based on spherical shapes with additions and modifications. I use Scarva Earthstone Professional Ashraf Hanna clay (PF520) which can withstand extreme thermal shock and also fires to a pleasing white finish. I hand build each pot, finishing the surface with three layers of slip which have been sieved through a 200 micron mesh. The first two layers are compressed and smoothed with several types of kidney and the final layer is then burnished with a polished quartz thumbstone. The process is extremely time consuming but the quality of the final surface is very important to me – not only because the process works best on a smooth surface but also because I believe that one of the characteristics of a “good” pot is that people just can’t resist touching it.
I bisque fire the pots to around 960 degrees in an electric kiln. Each pot is then dipped in a resist slip of 60% china clay and 40% flint. After 24 hours they are dipped again in a transparent raku crackle glaze and allowed to dry. The second firing takes place outside in a gas fired raku kiln. The final temperature of this firing is judged mainly by the appearance of the glaze. The pots are removed from the kiln with tongs and placed in a reduction chamber filled with hardwood shavings and other combustible material. After ten minutes the pots are removed and gently (very gently!) sprinkled with water.
At the end of a successful naked raku firing, the resist slip and glaze layers fall away, leaving patterns created on the surface of the pot by smoke – either through design (where the surface has been scored through or tape applied to the bisque pot) and/or serendipity (through the “crackling” of the glaze). The contrast between the control exercised in making the pot and the element of chance in every single raku firing never fails to both challenge and excite me.
The pots are protected from fingerprints by the application of a very thin layer of Renaissance polish.