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West System 406-7 Colloidal Silica is a premium epoxy thickening additive that expertly controls viscosity to prevent runoff on vertical and overhead surfaces. It enhances the strength, abrasion resistance, and consistency of epoxy fairing compounds, curing to a clean off-white finish. Ideal for woodworking and marine applications, this 5.5oz liquid filler is trusted by professionals and DIY enthusiasts alike for precision and durability.



















| ASIN | B005150RUW |
| Best Sellers Rank | #203,544 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #1,016 in Epoxy Adhesives |
| Brand | WEST SYSTEM |
| Brand Name | WEST SYSTEM |
| Colour | off-white |
| Compatible Material | Fibreglass |
| Container Type | Bottle |
| Customer Reviews | 4.9 out of 5 stars 82 Reviews |
| Full Cure Time | 24 Hours |
| Global Trade Identification Number | 00811343011505 |
| Included Components | FILLER COLLOIDAL SILICA 5.5 OZ |
| Item Form | Liquid |
| Item Package Quantity | 1 |
| Item Type Name | MARINE ACCESSORIES |
| Item Weight | 5.5 Ounces |
| Manufacturer | WEST SYSTEM |
| Manufacturer Part Number | 406-7 |
| Material | Colloidal Silica |
| Material Type | Colloidal Silica |
| Model | 406-7 |
| Number of Pieces | 1 |
| Other Special Features of the Product | Controllable viscosity, Prevention of epoxy runoff, Improved strength and consistency of fairing compounds |
| Special Feature | Controllable viscosity, Prevention of epoxy runoff, Improved strength and consistency of fairing compounds Special Feature Controllable viscosity, Prevention of epoxy runoff, Improved strength and consistency of fairing compounds See more |
| Specific Uses For Product | Woodworking |
| UPC | 811343011505 783847056576 |
| Unit Count | 5.5 Grams |
| Viscosity Level | High |
| Volume | 5.5 Fluid Ounces |
| Water Resistance Level | Water Resistant |
A**S
West system the best
Great filler from west system A++++++
M**L
Great stuff…not easy to work with, BE CAREFUL and go slow!!
This stuff works great!! It’s not easy to mix into the epoxy, it’s so insanely light, it just floats away if you’re not very very careful!! Add a little at a time, mix inside a garage or somewhere the wind can’t get to the mixing bowl. Once it’s mixed in, it does a great job thickening up the epoxy. Great for vertical surfaces as it really holds upright well once mixed to the proper thickness.
E**N
Versatile thickener for West Systems epoxy
I’ve used West Systems for probably 50 years. After the initial learning curve, it’s hard to use anything else. I use 406 on a majority of my glue joints. Measure it out into cut-down McDonalds cups using a gram scale for as little as 6 grams or for how many grams your container can hold. It makes a self-filling, durable joint in so many applications. Add as much 406 to epoxy for the thickness you need to make super strong joints.
M**E
Works well for fairings
Works well for fairing, very strong
T**U
Home run for my rustic wood flooring project, allowing me to fill large holes that unthickened epoxy would have run through
I used this to thicken the epoxy so it wouldn't run down through large cracks and nail holes in a rustic oak floor. Unthickened, the epoxy would disappear as quickly as I could inject it. This is a great system. It's very easy to mix this in until you get the desired thickness. I spread it on with a stick, smashing it down into the holes.
Trustpilot
5 days ago
4 days ago