Fillers for WEST SYSTEM EpoxySelecting Fillers

As a rule, use higher-density fillers when bonding higher-density materials such as hardwoods and metals. Any of the adhesive fillers are suitable for most bonding situations. Your choice of a filler for general use may be based on the handling characteristics you prefer. Fillers may also be blended to create mixtures with intermediate characteristics.

Filler Selection Guide

Adhesive Fillers vs. Fairing Fillers

Fillers are used to thicken the basic epoxy resin/hardener mixture for specific applications. Each filler possesses a unique set of physical characteristics, but they can be generally categorized as either Adhesive (high-density) or Fairing (low-density). Adhesive filler mixed with epoxy cures to a strong, hard-to-sand plastic useful in structural applications like bonding, filleting and hardware bonding. Fairing filler mixed with epoxy cure to light, easily sandable material that is generally used for cosmetic or surface applications like shaping, filling or fairing.


403 Microfibers for thickening epoxy
403 Microfibers

404 High-Density for thickening epoxy
404 High-Density

405 Filleting Blend for thickening epoxy
405 Filleting Blend

406 Colloidal Silica for thickening epoxy
406 Colloidal Silica

407 Low Density for thickening epoxy
407 Low Density

410 MicrolightTM for thickening epoxy
410 MicrolightTM