Tailor Epoxy Performance
WEST SYSTEM fillers are designed to modify mixed epoxy for fairing, filleting, bonding and gap filling applications. By selecting the correct filler, the epoxy mix can be adjusted for strength, sanding or handling characteristics.
Fairing, Filleting & Bonding
Different fillers are suited to different tasks. Some are designed for lightweight fairing and easy sanding, while others improve body, gap filling or structural bonding performance.
Adjust Mix Consistency
Fillers are added after the resin and hardener have been mixed, allowing the consistency of the epoxy to be built up to suit coating, filling, filleting or putty style applications.
Choose the Right Filler
Choosing the correct filler helps improve application control and final results. Lightweight fillers are ideal for sanding and shaping, while reinforcing fillers are better suited to stronger adhesive mixes.
Common Applications
- Fairing and smoothing surfaces
- Filleting corners and joints
- Gap filling before bonding
- Structural adhesive thickening
- Lightweight surface shaping
- Preparing epoxy blends for sanding and finishing
Technical Specifications
WEST SYSTEM Fillers & Hardeners Guide
Compare WEST SYSTEM additive fillers to choose the right fairing or bonding compound. Switch to the hardener guide to understand cure speed and resin ratios when using WEST SYSTEM 105 epoxy.
WEST SYSTEM Additive Fillers Breakdown
WEST SYSTEM fillers modify epoxy mixtures to change viscosity, strength and sanding behaviour for fairing, bonding, filleting and gap filling applications.
| Filler | Best For | Properties | Typical Use | |
|---|---|---|---|---|
| 410 Microlight | Fairing and shaping surfaces | Very low density, easy sanding | Lightweight fairing compounds for smoothing large areas | View Fillers |
| 411 Microsphere Blend | Filleting and gap filling | Lightweight filler with good body | Edge gluing, filling joints and shaping epoxy fillets | |
| 413 Microfibre | Structural bonding | High density fibre blend increases strength | Bonding components, reinforcing joints and structural repairs | |
| 417 Low Density Filler | Lightweight fairing putties | Microballoon based filler with easy sanding | Surface fairing and shaping cured epoxy before finishing |
WEST SYSTEM Hardener Comparison
WEST SYSTEM 105 Epoxy Resin is combined with a compatible hardener to control cure speed and working time.
| Hardener | Mix Ratio | Best For | Cure Profile | Typical Use | |
|---|---|---|---|---|---|
| 205 Fast Hardener | 5:1 | Fast turnaround jobs | Rapid cure with shorter working time | General repairs, bonding and coating | View Product |
| 206 Slow Hardener | 5:1 | General workshop use | Extended working time | Laminating, bonding and coating larger areas | View Product |
| 207 Special Coating Hardener | 3:1 | Clear finish work | Clear epoxy with moisture resistance | Timber coating, marine finishing | View Product |
| 209 Extra Slow Hardener | 3:1 | Large laminating projects | Extra slow cure for hot conditions | Fibreglass laminating and large structural work | View Product |
Compare Resin & Surface Systems
| Feature | Polyester Resin | Vinyl Ester Resin | Epoxy Resin |
|---|---|---|---|
| Typical use | General fibreglass laminating, repairs and moulding | Higher performance laminates and corrosion resistant structures | Structural bonding, premium laminates and advanced composite work |
| Cost level | Most economical | Mid to upper range | Highest cost |
| Mechanical strength | Good general purpose strength | Higher than polyester | Excellent structural performance |
| Water resistance | Good | Very good | Excellent |
| Chemical resistance | Moderate | High | High |
| Adhesion | Good for general laminating | Very good | Excellent across many substrates |
| Catalyst / hardener | MEKP catalyst | MEKP catalyst | Requires dedicated epoxy hardener |
| Best suited for | Cost effective fibreglass fabrication and repair | Marine hulls, tanks, pipes and demanding laminates | Premium marine, timber coating, structural bonding and advanced composites |
Polyester resin is often chosen for economical general fibreglass work, vinyl ester suits higher performance and chemical resistant laminates, while epoxy is the premium option for structural bonding and advanced composite performance.
| Feature | Gelcoat | Flowcoat |
|---|---|---|
| Primary purpose | Creates the outer cosmetic and protective surface in moulded fibreglass parts | Provides a protective topcoat for exposed fibreglass surfaces and repairs |
| Wax content | Generally unwaxed | Contains wax for tack free surface cure |
| Typical application stage | Applied first into the mould before reinforcement and resin | Applied as a finishing coat over cured fibreglass laminate |
| Finish quality | High quality moulded surface finish | Durable repair and finishing surface |
| Common uses | Boat hulls, decks, moulded composite parts, marine components | Boat repairs, internal lockers, bilges, protective topcoats and maintenance work |
| Surface cure | Remains tacky without laminate backing or additives | Cures tack free due to wax additive |
| Best suited for | New moulded parts requiring cosmetic outer finish | Repair work and protective finishing over existing laminate |
Gelcoat is primarily used as the outer mould surface finish for new fibreglass parts, while flowcoat is generally used as a tack free finishing coat for repairs, maintenance and exposed internal fibreglass surfaces.
Need CNC Cut Composite Panels?
Iron Link Distributors offers precision CNC machining for Coosa Bluewater composite boards and Divinycell structural foam cores. Send us your drawings, templates or CAD files and we can manufacture custom structural panels, composite inserts and precision cut core materials ready for installation.
- Custom CNC cut Coosa Board and Divinycell core panels
- Precision structural inserts, reinforcement plates and composite components
- CNC nested panel kits for faster installation and reduced waste
- DXF, DWG and PDF file formats accepted
- Quote based service for prototype, one-off or batch production
Perfect For
Boat transoms, bulkheads, deck cores, composite sandwich panels, cabinetry components, reinforcement plates, seating structures and marine or industrial composite parts requiring accurate CNC machining and repeatable precision.