Fumed Silica is an ultra-fine powder used to increase the viscosity (thickness) of resin systems. Adding a small amount of fumed silica to epoxy resin will significantly increase the thixotropic properties of the resin, effectively turning it into a gelcoat and allowing it to cling to sides of steep moulds without running.
Guidelines for Use
Fumed Silica requires significant agitation (stirring) to become fully mixed into a resin. Use of a mechanical stirrer will make the process quicker and easier but manual mixing is perfectly possible. For maximum effect, allow the Fumed Silica to soak in the resin for as much as a day before thorough mixing.
Fumed Silica added to resin at a ratio of 0.7% - 1% (by weight) will produce a thixotropic resin. 2-3% will produce a gelcoat consistency. Percentages up to 3%+ can be used to make a filler paste (additional filler powders may be required).
Please note the addition of Fumed Silica will reduce the clarity of clear resin systems meaning it is not ideal for turning clear laminating resin into a clear gelcoat.
Our Fumed Silica Thixotropic Powder is compatible with all popular resin systems, including polyurethane, epoxy and polyester.
Fumed Silica particles are incredibly small and light and will become airborne as soon as the material is scooped, moved or mixed. Always wear protective gloves and a dust mask when handling this product in its raw state.
Our Fumed Silica Thixotropic Powder is sold by volume and is available in 1litre (45g), 5litre (225g) and 10litre (550g) pack sizes. Please choose the pack size you require from the drop-down menu at the top of the page.
Please contact us if you would like to discuss larger quantities.