Fasco Epoxies Cabosil Fumed Silica Thickener – Epoxy, Gel Coat & Coatings, Gallon Tub

Overview

Fasco Epoxies Cabosil is a fumed silica thickener packaged in a gallon tub, designed to nudge viscosity without sacrificing workability. This versatile additive helps coatings stay where you apply them, offering a non sagging performance that many hobbyists and pros rely on for precise, smooth finishes across epoxy, silicone, paints, varnishes, and other liquids.

Key benefits at a glance

• Increases viscosity to reduce sag and drips on vertical surfaces
• Offers strong stability to help gel coats, epoxy, polyester and paints hold their shape
• Can strengthen coatings and act as a ceramic blanket rigidizer in compatible formulations
• Multi use thickener for epoxy resins and also suitable for rubber reinforcement when paired with fillers or fibers
• Hydrophilic surface aids resin wetting and uniform distribution

Real world use cases

In practice, Cabosil helps you achieve consistent film thickness on challenging shapes such as curved panels or edges. When integrated into epoxy systems, it can support a stable gel or enhance a non sagging finish. For gel coats and paints, it adds body without heavy compaction, resulting in even, predictable transfer from your tool to the surface.

• Epoxy resin assembly and castings
• Gel coats and polyester coatings
• Paints and varnishes applied to vertical or overhead surfaces
• Rubber reinforcement projects where sag prevention matters

How to use and best practices

Start with small increments and mix thoroughly, testing on a scrap panel before committing to a full batch. Add Cabosil gradually until you reach the desired viscosity and film integrity. Keep containers sealed and away from moisture to preserve performance.

• Combine with fillers or fibers to prevent sag while building thickness
• Pair with compatible resins for stable gel coats and coatings

Storage and safety

Store in a cool, dry place in the original gallon tub. Follow standard handling practices for fumed silica products and wear basic eye and skin protection when handling powders.