West System 404 High Density Filler

When maximum bonding strength is essential, WEST SYSTEM 404 High Density Filler is the professional choice. Developed specifically for structural bonding applications exposed to repeated loads and high stress, this premium epoxy filler transforms WEST SYSTEM epoxy into a powerful structural adhesive capable of handling the toughest marine and construction applications.

Designed for use with WEST SYSTEM 105 Epoxy Resin and all 200 Series Hardeners, as well as G/flex® 650 and G/5® Five-Minute Adhesive, the 404 filler creates a thick, non-sagging epoxy mixture that excels in bonding hardware, filling gaps, and forming high-strength structural fillets.

Unlike general-purpose fillers, WEST SYSTEM 404 is engineered for applications where failure is not an option. It delivers exceptional compressive and tensile strength, making it the preferred solution for installing winches, cleats, tracks, chainplates, hinges, deck fittings, and other hardware subjected to continuous mechanical loads.

Why Choose WEST SYSTEM 404 High Density Filler?

Whether you’re building a new yacht, restoring a classic boat, or carrying out structural repairs, 404 High Density Filler provides the strength and durability needed for long-lasting results.

Key Benefits

• Premium high-density epoxy adhesive filler
• Creates extremely strong structural bonds
• Excellent for bonding marine hardware and fasteners
• Ideal for high-load and high-vibration applications
• Bridges gaps without losing strength
• Produces strong structural fillets
• Non-slumping consistency for vertical and overhead applications
• Excellent compressive and tensile strength
• Compatible with WEST SYSTEM 105 Resin & 200 Series Hardeners
• Also compatible with G/flex® 650 and G/5® Adhesive
• Off-white cured colour
• Fine fibre powder for easy mixing

Ideal Applications

WEST SYSTEM 404 High Density Filler is recommended for:

• Boat building and yacht construction
• Marine repairs
• Hardware installation
• Winch and cleat bonding
• Chainplate installation
• Deck fitting reinforcement
• Fastener bonding
• Structural wood bonding
• Composite construction
• Gap filling
• High-strength fillets
• Reinforcing highly stressed joints

Mixing Instructions

After mixing the epoxy resin and hardener, gradually add WEST SYSTEM 404 High Density Filler until the desired consistency is achieved.

Typical filler loading:

• 35% by weight for a ketchup-like consistency
• 45% by weight for a mayonnaise consistency
• Up to 60% by weight for a peanut butter consistency suitable for gap filling and structural fillets

Technical Specifications

Available Sizes

WEST SYSTEM 404 High Density Filler – 250g

Ideal for:

• Small boat repairs
• Hardware installation
• DIY marine projects
• Woodworking repairs
• Occasional epoxy bonding jobs

WEST SYSTEM 404 High Density Filler – 1.75kg

Recommended for:

• Professional boatyards
• Yacht refits
• Large-scale composite construction
• Frequent epoxy bonding work
• Production environments

Why Buy from Cavo Yachting?

At Cavo Yachting, we supply genuine WEST SYSTEM® epoxy products trusted by professional boat builders, marine technicians, and yacht owners. Whether you’re installing deck hardware, repairing structural components, or building from scratch, WEST SYSTEM 404 High Density Filler provides the reliability and strength required for demanding marine environments.