Building a Hard Top Bimini for a Cruising Catmaran

Jessica and Ryan have a pretty solid cruising program aboard their Lagoon 410, considering they are raising two babies aboard their liveaboard catamaran. But when Ryan decides it’s time to rethink and construct a hardtop bimini for their boat, it is a bigger project than he had planned on tackling.  Working only outside in the elements, Ryan conquered windy days and a learning curve to successfully build this massive fiberglass structure that will replace a very tired old canvas version. This upgrade is built from 3/4 oz mat and 1708 fiberglass and plenty of Polyester Resin, Gelcoat, and luck! 

Ryan constructs a mold from wood that he uses to form his shape with Polyvinyl Alcohol (PVA) added as a release agent.  With some tricks up his sleeve, Ryan made fiddles for the top that he painted with Wet Edge Topside paint, and he discovered the magic of thickening gelcoat and Polyester Resin, techniques he was unaware of and learned mid-project.  It’s a massive project that will not only provide shelter from rain and sun, but will also house the solar panels and provide a catchment system for rainwater.

We love helping DIY boaters succeed with projects they didn’t think they were capable of, and our tech help and customer support line are here to offer guidance and help when you need it most. Tune in for the video of the week with Jessica and Ryan and subscribe to their channel for more of their boat work and adventures as they cruise the world. Enjoy!

1 comment

I admire you for the time and effort you put into this project. It’s beautiful. I have watched both videos three times and while making notes each time, one thing I did not hear you mention was the thickness of the wood for the female mold. I copied all the gallonage and other important things you mentioned. Just one more request if you don’t mind. Replacing my Sunbrella top every six or seven years because of the Sun, UV, and humidity here in FL, it is expensive. What size tubing would you recommend? I have standard 4 bow railing and worry I need stronger tubing for my project.

Thank you for your time and again, congratulations on a great Bimini top.

Jules Moquin

Jules Moquin

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