WEST SYSTEM® 105 Epoxy Resin

Low-Viscosity Epoxy Resin for Bonding, Coating, and Composite Work

WEST SYSTEM® 105 Epoxy Resin is a low-viscosity, solvent-free epoxy resin designed for reliable wet-out, strong bonding, and durable moisture resistance. Because it works with multiple WEST SYSTEM hardeners, you can tune working time and cure speed to suit the job. As a result, 105 suits everything from timber bonding and fibreglass repairs to reinforcing fabrics and mixed-material assemblies.

Product Short Description

Low-viscosity, solvent-free epoxy resin designed for strong bonding and coating. Ideal for marine repairs, composite laminates, timber work, and structural projects where moisture resistance and reliable cure matter.

Where 105 Fits Best

WEST SYSTEM 105 Epoxy Resin gives you a flexible foundation resin for many workflows. In addition, it supports both bonding and coating tasks without strong solvent odour. Therefore, it works well when you want strength, moisture resistance, and repeatable results.

Use 105 when you need:

• Strong timber bonding and sealing

• Fibreglass repair and reinforcement wet-out

• Composite laminating and structural bonding

• Coating work where moisture resistance matters

Hardener Options and Use Cases

Because cure speed depends on hardener choice, WEST SYSTEM offers several options:

205 Fast Hardener

Choose 205 when you need a faster cure, especially in cooler conditions. It can cure down to 10°C, which helps when the temperature drops.

206 Slow Hardener

Choose 206 when you need longer working time or when you work in warmer conditions.

207 Special Coating Hardener

Choose 207 for coating applications where clarity and a natural timber finish matter. It includes a UV-inhibiting additive, however you still need a proper UV topcoat for outdoor exposure.

209 Extra Slow Hardener

Choose 209 for very warm or humid conditions, or when you want extended working time.

Mix Ratios

Mix ratio depends on the hardener family, so keep it simple and accurate:

• 105 + 205 or 206: 5:1 (resin:hardener) by volume and weight

• 105 + 207 or 209: 3:1 by volume (3.5:1 by weight)

Important: Do not change the hardener ratio to control cure time. Instead, pick the right hardener for the conditions.

Typical Applications

Because 105 adapts to many processes, engineers and builders use it across:

• Marine and boatbuilding (repairs, bonding, sheathing, sealing timber)

• Wind energy and renewables (composite repairs, bonding fixtures, tooling work)

• Aerospace ground tooling and jigs (durable bonded assemblies)

• Automotive and motorsport (composite repairs, brackets, bonded fixtures)

• Construction and infrastructure (timber sealing, structural bonding, moisture protection)

• Drone manufacturing and robotics (light composite wet-out and bonded joints)

These uses make sense because 105 wets out fabrics well and cures to a strong, moisture-resistant solid.

Technical Specifications

Uncured Properties

Typical Cured Mechanical Properties (Neat Cast)

WEST SYSTEM 105 Engineering Data

Storage and Handling

Store the WEST SYSTEM 105 Epoxy resin and hardeners in original sealed containers at 15°C to 32°C, out of direct sunlight. When you store them correctly, they keep for 2 years.

Use gloves and eye protection, and work with good ventilation.

Why Choose Enhanced Composites

Enhanced Composites supplies epoxy systems that builders trust for real workshop conditions, not just lab numbers. In addition, we help customers choose the right hardener for the temperature, job size, and finish goal. Because of that guidance, you get more consistent cure results and fewer rework headaches.

FAQs

Which hardener should I choose for warm weather?
Use 206 Slow for more working time in warmer conditions. If conditions are extremely warm or humid, choose 209 Extra Slow.

WEST SYSTEM 105 Epoxy

Can I use 105 for clear timber coating?
Yes. Pair 105 with 207 Special Coating Hardener for coating applications where clarity matters. However, add a UV-protective topcoat for outdoor exposure.