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West Systems 403B Microfibers Epoxy Thickening Additive 20 lb

Manufacturer

West Systems

<p>Founded in 1969 by brothers Meade, Joel, and Jan Gougeon in Bay City, Michigan, West System emerged from a shared passion for building sailboats and iceboats. What began as experiments with epoxy technology in the late 1950s evolved into a collaboration with chemists at Dow Chemical Company's epoxy lab, resulting in formulations that could serve as both adhesive and coating. The formulations developed became the basis of the WEST SYSTEM group of products introduced in 1971, revolutionizing wooden boat construction and marine bonding applications.</p><h3>Pioneering Marine Epoxy Technology</h3><p>West System Epoxy was created by Gougeon Brothers—sailors, builders and formulators who know the engineering and chemistry required for high-performance composite structures. In 1970, the brothers launched Adagio, the first large, all epoxy bonded and sealed wooden boat built without the use of fasteners, demonstrating the structural integrity their epoxy formulations could achieve. For over 50 years, WEST SYSTEM epoxy has been the marine industry's trusted brand for versatile, high-quality epoxy resin systems, expanding from marine applications to woodworking, composite construction, and general repair.</p><h3>Comprehensive Product Lineup</h3><p>The company's signature <a href="/7644-west-systems-west-system-products-201176">West System Products</a> include their renowned two-part epoxy systems featuring 105 Epoxy Resin paired with specialized hardeners, fillers, and additives. West System Epoxy is a versatile, high-quality, two-part epoxy easily modified for a wide range of coating and adhesive applications, especially suited for marine applications requiring superior moisture resistance and high strength. The modular system allows users to customize working time, cure characteristics, and physical properties by selecting different hardeners and incorporating various fillers for specific bonding, fairing, or filleting applications.</p><p>Beyond traditional epoxy resins, West System offers specialized solutions like <a href="/7644-west-systems-vinyl-sealant-repair-kit-19328">Vinyl Sealant Repair Kits</a> designed for quick repairs and sealing applications. The brand also provides an extensive selection of <a href="/7644-west-systems-maintenance-parts-accessories-200647">Maintenance Parts & Accessories</a> including metering pumps, mixing pots, application tools, and roller covers specifically engineered for epoxy work.</p><h3>Engineering Excellence and Quality Standards</h3><p>Not all epoxies are created equal—epoxy brands can vary widely in formulations, quality of raw materials, and suitability for marine environments, and it's much more difficult to balance all of the physical and mechanical properties necessary for a versatile, high-quality marine epoxy. West System epoxies are marine-grade and undergo rigorous testing to ensure their strength, making them suitable for applications ranging from boat building and repair to composite construction, woodworking, and structural bonding in demanding environments.</p><p>As an employee-owned, family run organization operating since 1969, West System maintains the same commitment to quality and innovation that drove the Gougeon brothers' original experiments. Their products bond tenaciously to wood, fiberglass, carbon fiber, metals, and many plastics, providing excellent moisture resistance and creating durable, long-lasting repairs and construction that withstand the harshest conditions.</p>

Part Number

403B
06/01/2036 3:53 AM
Sale Price

$316.76

In Stock (10+)

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Usually delivered within 2 days

free shipping

FREE SHIPPING

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

West System 403B Microfibers is a fine fiber blend designed as a thickening additive for epoxy resin systems. This off-white filler builds volume quickly and blends easily to create versatile adhesive compounds, making it especially effective for bonding wood and other porous materials.

Key Features:

  • Fine fiber blend that mixes smoothly into epoxy resins without clumping
  • Excellent gap-filling properties for joints and uneven surfaces
  • Maintains superior wetting characteristics for strong penetration into wood grain
  • Creates a high-strength structural adhesive when mixed with epoxy
  • Multi-purpose additive suitable for laminating, filleting, and bonding applications
  • 20 lb container provides substantial volume for large projects or professional use

When added to West System epoxy resins, 403 Microfibers create a strong, easily worked paste that's ideal for filleting, bonding, and filling voids. The fiber blend maintains the epoxy's ability to wet out surfaces while adding body and reducing sag on vertical surfaces. This additive is particularly valued in marine applications, woodworking, and composite fabrication where strong structural bonds are critical.

Products specifications

Type

Filler

easy to order

Shipping is expensive

very hard to find parts. was very happy you had them.you won my business.thanks

Nice site

The resonator I ordered arrived at my house slightly bent, but I called Autoplicity and they sent a replacement by next-day-air, so I was happy about that. It's a little hard to reach people there when you need to get a problem resolved, but in the end it all worked out.

Very user agreeable

Found exactly what I needed at a reasonable price!

Great prices hence why after a search on my desired part why I showed up at their store. Had great communication with their staff throughout the entire process.

Quick and easy transaction, Thanks

Easy shopping experience

good prices, well-designed website. stuff got here like lightning, nicely packaged. will def use again.

Good

EASY

Super Low Prices Fast shipping and they have all kinds of mods parts. I am a bargain shopper and i am super satisfied with price and shipping cost take that FLEE BAY!!!!

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