• Resin Type: Orthophthalic Polyester Laminating Resin
• Brand / Grade: Silmar 249 (Clear)
• Color: Water-clear
• Viscosity: ~650 cps @ 77°F (25°C)
• Gel Time: ~16 minutes @ 77°F with 1% MEKP
• Cure Characteristics: Medium reactivity; tack-free surface when used with surfacing wax
• Mix Ratio: 1% MEKP (10 cc per quart / 40 cc per gallon)
• Density: ~1.11 g/mL
• Shelf Life: ~6 months (stored in a cool, dry place)
• Packaging: Available in ½ pint, pint, quart, and gallon cans

Silmar 249 Clear Polyester Surfboard Resin - by volume

• Surfboard Industry Standard – Widely used by surfboard manufacturers for its clarity, strength, and reliability.
• Crystal-Clear Finish – Formulated for a transparent, glossy surface ideal for laminating and hot-coating.
• UV Inhibitors Added – Helps resist yellowing and improves outdoor durability.
• Excellent Wet-Out – Flows easily into fiberglass cloth for strong, bubble-free laminations.
• Versatile Use – Suitable for surfboards, composite laminates, and clear-finish fiberglass applications.
• Catalyzes with MEKP – Standard 1% mix ratio for consistent curing.

Silmar 249 Polyester Resin - MSDS

MEKP (Methyl Ethyl Ketone Peroxide) - MSDS