Sea-Line Epoxy Filler with Fiberglass 2:1 – Ultra-Strong Filler for Deep Repairs

Sea-Line Epoxy Filler with Fiberglass is the heavy-duty “muscle” among fillers, designed for the most demanding repair jobs. The filler’s fiberglass-reinforced components impart extra strength to the mix and allow very thick layers to be applied without risk of collapse or cracking in the repair. This makes the product an excellent choice for filling deep holes, large cracks, or structural voids where ordinary fillers might lack sufficient strength.

The combination of a lighter base (component A) and a fiberglass-filled hardener (component B) provides a balance between ease of application and maximum toughness. The filler is mixed at a 2:1 volume ratio (100:50 by weight) and has about a 50-minute pot life at 20°C – giving you ample time to work. It reaches a sandable hard cure in ~16 hours at 20°C. The cured filler is light grey in color, with increased hardness and strong adhesion to the substrate.

• 0.75 kg kit: Contains A + B totaling 750 g (base + hardener) – ideal for typical repairs of deep scratches, holes, or osmotic damage on small to medium boats. Convenient for use in a DIY setting while still delivering maximum strength in the fix.
• Large kit: For big projects, Sea-Line offers component A (5 kg resin) and component B (2.5 kg fiberglass hardener) – yielding about 7.5 kg of filler. This is perfect for professional boatyards handling major repairs or refits on large vessels that require a substantial volume of filler.
• Application: Apply with a spreader/putty knife to a well-prepared surface (either primed or bare but cleaned and abraded for good adhesion). This filler works effectively on GRP/fiberglass, wood, and metal, making it versatile for yacht hulls, keels, transoms, and more. It can be used both above and below the waterline (the epoxy base is waterproof once cured).
• Strength and bonding: Thanks to the fiberglass content, this filler can also be used for bonding components – for example, when installing reinforcing elements, filling around bolts/frames, or during modifications where a very strong joint is needed. Once cured, the repair can withstand significant loads and vibrations.
• Finishing: After sanding the cured filler, apply an epoxy primer over the repaired area to seal and level it, followed by an appropriate topcoat (polyurethane paint or antifouling for underwater sections). This will ensure long-lasting protection and a smooth visual transition between the repaired spot and the original surface.