When mixing your casting slip, the approximate amount of dispex to weight of dry clay or powder can be calculated as follows,.16% x grams of powder. Only use 80% of this amount, just in case it proves too strong, but you can add the rest later if needed.
However, when making larger quantities of slip, we first recommend mixing the clay with water to achieve the right specific gravity before adding the deflocculant. You should aim for a specific gravity of around 1.7 to 1.8, for information on how to measure this, see our product attachments.
If your casting slip is already mixed with water, once again make sure it has the right specific gravity then add a drop of the dispex until it is flowing to your desired consistency. In this instance only add small amounts of deflocculant.