Have you ever mixed up a glaze only to find it settled into a rock-hard mass at the bottom of your bucket the next day? Have you worked with a finicky glaze that just always seems to be a little bit too thick – or too thin? Additives, deflocculants, and gum solutions can help with all of these problems, and more. This category of products consists of various materials that can be added to glazes or casting slips in small amounts to achieve specific effects.
Additives – Additives for glazes consist of Spectrum’s glaze thinner and suspender, and Amaco’s Suspend-Aid. These are commercially-produced products that will come to you in pint form. Suspenders will prevent your glazes from settling at the bottom of your glaze bucket – just add the suggested amount, mix well, and glaze with ease! If you’ve ever mixed up a glaze that you just can’t seem to get to the proper thinness, Glaze Thinner is a product that could work for you.
Deflocculants – When clay or glaze materials are suspended in water, they behave in one of two ways. In an acidic environment, the particles may be attracted to each other, causing clumping, settling, or an otherwise lack of consistency. This state is known as ‘flocculation’. The second way clay particles can behave is in a state of DE-flocculation. In this case, that attractive charge that makes flocculation occur has been neutralized, which causes particles to remain in suspension. No gathering in groups, no settling to the bottom, all due to electrostatic attraction. The end result of deflocculation is a smoother glaze or slip that won’t settle as much – or, in some cases, at all! This also results in a less viscous solution. As such, a deflocculant is a substance that causes a reduction in viscosity – and may also contribute to the overall homogeneity of your mixture. A deflocculant basically increases the repulsion between glaze particles, causing them to better remain in suspension.
Gum Solutions – Gum solutions can be used to bring old, hardened glazes back to their original consistency. These organic additives can, however, decay in glaze solutions over time (unlike the inorganic materials that make up the glazes themselves), so keep that in mind when adding them to a glaze.