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PRACTICAL INFORMATION
All clays are formulated for the Craft Potter and are usually supplied in plastic condition in 10kg polythene bags with approximately 22% moisture or throwing consistency and 17-18 % moisture content for "RAM" (TM) pressing  consistency. Special bodies for industry are available. Our production of  moist clays is controlled by our desire for consistency. Controlling the production from receipt of bulk crude clays to the final blending of the recipes in wet form and then storing of filter cake prior to extruding in de-airing pugmills, enables us to ensure there is consistency from batch to batch. The following  hints may prove helpful to some potters especially those with no previous experience of Walker Ceramics clay bodies. Comments refer to both stoneware and earthenware clays unless otherwise stated.
Ageing will dramatically improve the working qualities of any clay, therefore it is an advantage to keep a 3-6 month supply on hand, if space and finances permit.
All Walker Ceramics bodies are extruded through porcelain and de-airing pugmills. This eliminates the need for time consuming preparation before throwing. As a block is cut into pieces of the required size each ball can be formed by gentle kneading on a clean bench top. Lengthy time in kneading on an absorbent surface is only necessary if the clay is too soft. When reclaiming leftovers, the clay should be kneaded for a short time and then wedged until even in consistency. Faulty wedging is the cause of splits and cracks that can occur on any part of a pot - during throwing, drying or firing.
Air pockets can cause splits, cracks and bloats. They are easily noticeable during throwing - clay with any air pockets should be re-wedged - however if only one or two appear in a pot they can be pierced with a pointed tool, to allow the air to be gently pressed out with the fingertips.
To eliminate "S" cracks from the base of the pots (this occurs mainly with open stoneware clays) the following hints could prove helpful. When centering, the clay should be formed into a cone as high and as narrow as possible and then pressed onto the wheel head into a flat perfectly centered ball. This practice, like wedging, helps to even  out consistency and also arranges the small particles into a spiral which gives extra strength when the ball is opened out into a cylinder. Next the base must receive the same amount of compression as the walls. So when the ball is opened out the fingertips should be run over the base firmly several times before further attention is given to the sides. Any water in the bottom of the pot should be removed as soon as possible. If allowed to collect there and saturated the thin base, star and "S" cracks can result.
When compressing the base, an effort should be made to eliminate the small "nipple" of clay that can form in the centre of the base - as this is usually the cause of small "S" cracks. The thickness of the base is also crucial. A good guide is to make the base, of even the largest pots, as thin as possible. As soon as the ware is firm enough, it should be turned. After the necessary amount of clay has been turned out of the base, it can be further compressed form the outside (care should be taken not to press your fingers right through). However, the tension resulting form  pressing the base slightly inwards (especially on closed in forms) will give extra strength and further eliminate the possibility of "S" cracks.
Finished pots should be dried upside down or on their sides out of draughts or direct sunshine. Too quick or uneven drying can cause distortion and cracks. (Special attention must be given to the 5A Stoneware range in this respect while on the other hand No 10 and PB103 hardly ever suffer from forced drying). To avoid warpage, flat ware (bowls, platters, etc) should always be thrown on batts and not handled until dry enough to turn.
Throwing "off the hump" may be a problem  with most stoneware bodies, however  No.10 Stoneware and PB103 have proved successful . This technique makes it impossible to give the base the necessary compression, thus causing heavy losses due to "S" cracks. For the same reason, goblets with solid stems in most stoneware bodies could prove to be a disappointment. Appendages such as handles, spouts, knobs, etc., should be attached as soon as the bases are turned. Both surfaces should be  roughened then water or slip of the same clay applied before both parts are pressed firmly together and finally modeled to give a neat appearance.
Knobs are frequently turned from the "waste" clay leftover form bowl-shaped lids. This practice can cause "S" cracks across large bulky knobs. To overcome this problem, knobs can be thrown from a small ball of clay attached to the lid in in the usual manner. Yet even thrown knobs can cause problems - if air is trapped between the knob and the lid, the knob will fall off during either drying or firing. A small hole drilled form the inside of the lid into the knob is a good safety measure.
Unusually long and fine handles tend to dry out and shrink long before the pot that they will be attached to. To avoid broken handles a thin strip of plastic should be wrapped around them - this will even out the drying. The plastic can be left in position until the bisque firing.
Over sponging ware during throwing will expose the grog and result in an unpleasant sandy finish - this can be annoying on the rims of drinking vessels as well as possibly causing shelling of glazes. By finishing off edges with a small piece of chamois a smooth finish will result.
Bodies such as White Pottery, White Modelling, Fine Terra Cotta 60# , Super Fine Terra Cotta 120# , Ironstone, Pink Earthenware, White Earthenware, Auscraft Ultrawhite,  Superior White Porcelain , No 10 , PB101,PB 102 , PB 103 and Vitreous China are all suitable for fine work because of their small particle size giving a smooth finish.
Turning can also cause a rough finish, this can be smoothed out by running a modeling tool or thumbnail over the pot while it is rotating on the wheel.
Marbled and striped effects are usually achieved by wedging bodies of different colours together. The clay thus prepared is re-wrapped and allowed to stand for some time before use. However, cracks can occur due to the differences in shrinkage. A safer way of achieving the same results is to use the same body - staining part of it and leaving the rest its natural colour. If correctly wedged, no separation should result using this method e.g. 5A White, Red and Dark can be successfully marbled.
Finally, most losses during the bisque fire can be eliminated with a little patience. A rate of 50°C per hour during the early stages of firing and 150°C during the later part is recommended. Also remember pots that are not completely dry or too heavy are a danger to all other pots around them.
To many potters,  glazing requires as much care and thought as the actual making of pots. Even the most highly recommended glazes should be tested to see how they behave in your own kiln, before being applied to pots.