Dalchem 421 Epoxy System - Multipurpose Laminating & Casting Epoxy

Dalchem 421 is a solvent-free, liquid epoxy resin system specifically designed as an industrial-grade laminating and tooling epoxy that cures at room temperature. Its low viscosity allows easy wetting of fibreglass and fillers, making it ideal for laminating, casting, adhesive bonding, and general-purpose applications. The system cures to form a hard, high-impact-resistant material with excellent mechanical properties, widely used in woodworking, boatbuilding, foundry pattern making, and general composite fabrication.

Features & Benefits

• Solvent-free formulation – low odour and easy handling
• Low viscosity – excellent flow and filler incorporation
• High-strength bonding for wood, composites, and tooling
• Room-temperature cure – no ovens required
• Versatile – laminating, casting, bonding, and repairs

Typical Applications

• Fibreglass laminating and boatbuilding
• Woodworking adhesives and joinery
• Casting of foundry patterns, plugs, and checking tools
• General-purpose resin laminating and repairs
• Composite component fabrication

Technical Data

• Mix Ratio (by weight): 100 parts Resin : 25 parts Hardener (5:1)
• Pot Life (500 g @ 25 °C): 50–60 minutes
• Thin Laminate Gel Time (25 °C): 4.5 hours
• Demould Time (25 °C, 15 mm cast): 12 hours
• Mixed Viscosity (mPas @ 25 °C): 850

Cured Properties

• Shore D Hardness: 84
• Heat Distortion Temperature (24 hrs @ 25 °C): 50 °C
• Compressive Strength: 55 MPa
• Flexural Strength: 81 MPa
• Modulus of Elasticity: 3.1 MPa
• Linear Shrinkage: 0.1–0.3%
• Tensile Elongation: 9%

Packaging

Supplied as matched resin and hardener pack sizes suitable for professional and hobbyist use.

Safety

Consult the Data Sheet before use. Wear appropriate PPE and follow safe handling practices.

Technical Data Sheet