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The BEST Fiberglass Deck Core Materials (And How To Choose)

September 4, 2023 · 31 min · 67K views

What this video covers

Restoring a water-damaged fiberglass deck requires selecting a core material based on nine mechanical and practical criteria: shear strength, compression strength, shear strength-to-weight ratio, density, water resistance, insulation, workability, cost, and availability.3:17 A deck functions as a 360-degree I-beam, where the top and bottom fiberglass skins act as flanges and the core resists shear forces.2:21

Plywood, specifically marine-grade BS-1088 or BS-6566, offers high workability but remains susceptible to rot if deck penetrations leak.8:26 Balsa provides a superior shear strength-to-weight ratio due to its vertical grain orientation, which also facilitates resin bonding, though it absorbs significant resin and can hold 600% of its weight in water when saturated.12:47 G10, a compressed fiberglass and epoxy panel, offers the highest shear and compression strength but is prohibitively heavy and expensive for full-deck coring.15:41 Proper maintenance of deck penetrations using epoxy-plugging techniques remains the most effective way to prevent core failure in existing balsa or plywood decks.14:53

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Boats in this video

Liberty 458Their boat

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