Colloidal Silica is an epoxy thickening additive used to control the viscosity of the epoxy. It prevents epoxy runoff in vertical and overhead joints. This is a very strong adhesive filler. It creates a smooth mixture, ideal for general epoxy bonding and filleting. 406 can be used to improve the strength, abrasion resistance, and consistency of epoxy fairing compounds. The result is a tougher, smoother surface.
