Page 644 - Lewis

West System Epoxy 643

Fillers and Additives

No. 403 Microfibers No. 406 Colloidal Silica

FIG 5509b
FIG 5506b
406 Colloidal Silica is a thickening additive used to control the
viscosity of epoxy and prevent epoxy runoff in vertical and
Our "workhorse" filler, 403 Microfibers, is made of fine cotton
fibers and is used as a thickening additive with resin/hardener overhead joints. 406 is a very strong filler that creates a
to create a multi-purpose adhesive. Microfibers and epoxy are smooth mixture, ideal for general bonding and filleting. It is
particularly effective in bonding wood. Epoxy thickened with also our most versatile filler. Often used in combination with
microfibers provides good gap-filling qualities while retaining other fillers, it can be used to improve the improve strength,
excellent wetting and penetration capabilities. Microfibers are abrasion resistance, and consistency of fairing compounds,
used primarily in bonding and gap-filling applications. resulting in a tougher, smoother surface. Color: Off-White.
Microfibers are non-toxic, but care should be taken to avoid No. Each Size Case
inhalation. Color: Off-White. 406-2 $12.25 1.9 oz. 24
No. Each Size Case 406-7 29.30 5.5 oz. 12
403-9 $12.20 6.0 oz. 24 406B 265.65 10 lbs. 1
403-28 27.85 20.0 oz. 12
No. 407 Low-Density Filler
No. 404 High-Density Filler Microballoon Blend

FIG 5510b

FIG 5507b 407 Low-Density filler is a blended Microballoon-based filler
used primarily to make inexpensive filling and fairing putties
which are easy to sand or carve while still being a reasonably
404 High-Density filler is a thickening additive developed for good engineering material on a strength-to-weight basis. It
maximum physical properties in hardware bonding where can also be used as a thickening additive for bonding veneers
high-cyclic loads are anticipated. It can also be used for fillet- and in low-stress structural applications where light weight
ing and gap-filling where maximum strength is necessary. May can be beneficial. Good feathering and won't sag. Color: WEST SYSTEM EPOXY
be added to the resin/hardener at a rate of 20 to 30% by Reddish-Brown.
weight, depending on the viscosity needed. Color: Off-White. No. Each Size Case
No. Each Size Case 407-5 $18.05 4 oz. 24
404-15 $15.95 15.2 oz. 24 407-15 43.20 12 oz. 12
404-45 36.95 45.6 oz. 12 407B 479.20 14 lbs. 1
404B 256.70 30 lbs. 1 WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov

FILLER APPLICATION CHARTS No. 405 Filleting Blend
FILLER APPLICATION FILLER
MOST SUITABLE=4 403 404 405 406 407 410
LEAST SUITABLE=0
LAMINATING 4 2 2 3 2 0

BONDING 2 4 2 3 1 0
FIG 5508
FAIRING 0 0 0 0 3 4
405 Filleting Blend is a strong, wood-toned filler for use in glue
HARDWARE BONDING 2 4 2 3 0 0
joints and fillets on naturally-finished wooden interiors. Mixes
easily with epoxy and lets you create fillets that are smooth
FILLETING 1 2 3 4 3 0 and require little sanding. Color is a consistent tan so it can be
used to modify the shade of other West System fillers.
Various fillers can be combined to achieve No. Each Color Size Case
desired working properties. 405 $18.25 Tan 4 oz. 24
ALWAYS MIX RESIN & HARDENERS FIRST BEFORE ADDING FILLERS AND ADDITIVES
For superior holding strength it is always best to "Wet Out"the substrate with your resin/hardener mixture
before adding any filler.