G-10 Backing Material

We’re fully in countdown mode here, methodically ticking off projects almost as fast as we’re adding them to the list. While most of the deck hardware is back on, there are a few last bits to install - and many of those require backing plates of some kind.

Backing plates are kind of like oversized washers (though we use washers as well). They spread the load of a fastener, ensuring that the stresses aren’t just in one small place. Using washers and backing plates is smart for a lot of reasons.

Washers are a given, something you can find in any hardware store worthy of the name. But backing plates? What do you use for those? A lot of the old backing plates on Calypso are plywood, which is a good first step for sure. But plywood can compress over time and is susceptible to rot, not something we want.

Enter G-10.

Various pieces of G-10 await use as backing blocks.

G-10 (aka garolite) is basically layers of fiberglass that’s held together with epoxy resin, but done so in a compressed manner. This results in an extremely strong product that’s essentially waterproof and chemically resistant. You can buy G-10 sheets up to an inch thick; if you needed it thicker, you could always laminate a couple together.

It’s smooth. Drillable. Workable with a router or jigsaw. Takes epoxy like a champ. Paints well.

Despite the fact that Calypso is a traditional boat with a lot of wood on her, we’re slowly moving to more durable material as we see the opportunity. Using G-10 as backing blocks is one of those such opportunities.

G-10 backing block helping support a deck cleat.