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Walker Ceramics has an extensive range of prepared casting slips.
Preparation involves only the addition of measured amounts of water and deflocculents.  
We strongly recommend that casting slips should be tested for suitability prior to any bulk use.
All slips are available in 5 litres, 10 litres, and bulk quantities  for your own production.
**Slips may be coloured with the addition of stains suitable for clay bodies.
Superior White Porcelain (AB10)
A fantastic new Australian made porcelain. All Australian materials. Superb whiteness and strength. Proven throughout Australia as a throwing, pressing, casting and hand building body. 
Renowned for it's consistency and workability.
No.10 Stoneware (AB100)
Fires between 1240-1300°C. Excellent glaze colour development on this white body. It is suitable for both Middle Fire and Stoneware glazes.
PB103 (AB103)
The classic throwing and pressing body made directly into casting slip. A fine white stoneware firing to a white colour at 1300 C.  Beautiful workability and excellent glaze fit at Cone 8 -10.  Biscuit at 1000 - 1060 C Glost 1280 - 1300 C. 
White Earthenware / Middle Fire (AB300) 
The body should be biscuit fired at 1000°C (minimum) and then appropriately glazed and fired from 1060 - 1250°C. This will cover the full range of our standard Earthenware and Middle Fire glazes.
CB1 (AB400)
This body has excellent pouring and working properties and high green strength. Fires  white. 
Biscuit at 1060°C to 1100°C  Orton Cone 04 - 03 .
Glost to 1000°C  - 1060°C  Orton Cone 06 - 04.
Suits all Hobby Ceramic Glazes. Especially WHG400 Clear Gloss.
Terra Cotta (AB405)
A beautiful rich red Terra Cotta slip. Suits most Earthenware and Hobby glazes. Biscuit at 1000°C to 1100°C  Cone 06 - 03 . Glost to 1000°C  - 1060°C Orton Cone 06 - 04. 
Auscraft Ultra White (AB450)
This body has excellent pouring and working properties and high green strength. Fires to  Ultra white . 
Biscuit at 1060 to 1100°C  Orton Cone 04 - 03 .
Glost to 1000  - 1060°C Orton Cone 06 - 04.
Suits all Hobby Ceramic Glazes. Especially WHG400 Clear Gloss.
Vitreous China (AB475)  **** NEW ****
This body has been designed for the people who want Porcelain / Stoneware strength with the brightness of Earthenware colours at Earthenware temperatures.  Biscuit at 1000 to 1060°C  Cone 06 - 04 . Glost to 1150  - 1170°C Orton Cone 1- 3. 
Bone China (AB505)     **** NEW ****
Fine quality AUSTRALIAN made Bone China. Beautiful whiteness and translucency second to none!! Biscuit 1000 C Glost to 1250 C. 
Limoges  97975 - 1220 C (AB511)
The classic European porcelain now available in Australia. Beautiful workability, whiteness, translucency and strength. Available in 5 litres, 10 litres, and bulk quantities  for your own production.
Limoges  CM10 - 1300 C (AB530)
The classic European porcelain now available in Australia. Beautiful workability, whiteness, translucency and strength. Available in 5 litres, 10 litres, and bulk quantities  for your own production.
TECHNICAL DATA

* AVAILABLE IN PLASTIC   ◄ AVAILABLE IN POWDER

Deflocculants
The amounts of Sodium Silicate or Dispex N40 added to a casting slip are very critical and too much or too little may each result in the slip being too thick. If this happens, take a 1 litre sample of the slip and add one or two drops of Dispex N40. If the slip becomes thinner after stirring then this shows that more is required to achieve good fluidity. If the slip becomes thicker then this shows that too much has been added already. Therefore more clay and water needs to be mixed into the slip in the same proportion as given in the casting recipe – no more Sodium Silicate or Dispex N40. The recipe can depend on the quality of the water supply, which may vary from one location to another and also may be affected by minor variations in the body’s raw materials.
Maturing the slip
On standing overnight the slip may thicken up slightly. This will easily reblend when mixing is resumed, even by hand. We recommend that at the end of the day's production a thin film of water, approximately 2mm thick, is placed on top of the slip. This will reduce water evaporating from the mix, especially in warmer weather. Simply mix again the following day.
Litre Weight Checks
The most important part of successfully mixing casting slips is getting the correct litre weight. For accurate and easy litre weight measurement contact Walker Ceramics for a Litre Weight Bottle and chart.

Recycling Scrap
Great care is needed to avoid contamination, particularly from plaster moulds. Scrap should be kept in sealed containers in a plastic condition. Dry scrap will promote air inclusion in the slip. Recycle by adding a maximum of 20% of scrap. More than 20% can effect the quality of the slip. We recommend adding Barium Carbonate (BaCO₃) to the slip to remove sulphates, which may cause peeling faults. The amount of Barium Carbonate to add should be 0.1% (25gm per 25 kg bag) of the total dry weight of clay and scrap.
Faults and Remedies
Everybody who casts suffers from time to time from some form of casting trouble. Walker Ceramics' experience of the industry, combined with the extensive work done on casting slips in our laboratory has enabled us to connect the various faults with measurable properties of the slip.
Of course, other factors besides slip properties can cause casting faults, but usually they can be easily noticed; for example, wet moulds causing slow casting, careless filling causing 'pinholes' or 'casting-spot', etc.,
The table shown gives a brief description of each of the common troubles and the suggested remedies. This only gives the direction in which to move and it is up to the individual to determine how far they need to go.
Say you were suffering from flabbiness and you increased the Dispex addition to correct this then found that you began to get brittle ware with casting spot, then you would know you had gone too far. The following table will help you in recognizing and fixing common problems. Thixotropy is the property of slips becoming thicker when they are at rest i.e. "thixotropy too high" means that the slip thickens up very quickly!