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DIY Pottery Wedging table + Plaster fact sheet.
John Britt: Basic method for making a raised slip a.k.a. thickened slip, joining slip, trailing slip. You are basically making the ph basic to deflocculate and make the ph acid (Epsom Salts) for flocculation. To make a denser slip (adding clay without adding water), first deflocculate; using a deflocculant allows for increasing the specific gravity without decreasing viscosity.