New Zealand kaolin based slip casts at 1mm thickness. How?

Wednesday 5th February 2014

This is Polar Ice casting, a New Zealand Halloysite based cone 6 insight-live.com/glossary/233">translucent porcelain. The base body recipe would never have enough plastic strength to pull itself from this mold without tearing. But the addition of 1% Veegum gives it amazing strength. This dried cast bowl measures 130mm in diameter and 85mm deep, it only weighs 89 gm! The slip was in the mold for only 1 minute before pour-out. Of course, there is a price to pay for adding the Veegum: Increased casting time and more difficult deflocculation. Regular bentonite can be used in most bodies, but for super-whites like this, Veegum (or equivalent) is the choice. Testing is needed to determine what percentage gives the needed strength yet does not increase the casting time too much. The polar ice information page at plainsmanclays.com has very good information, under the heading “Casting Recipe”, about the challenges and trade-offs of using this kaolin in casting bodies.

Pages that reference this post in the Digitalfire Reference Library:

New Zealand Halloysite, Formulating a Porcelain, Slip Casting, Deflocculation

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