Building a Plywood Catamaran 

Ah thank you 🍺

Wharram designs are great. The flexibility allowed through the lashing of the beams and deck makes them more resilient in rough water. Multi hulls have a lot to offer in their efficiency - great for solar. What is the company called that is making the Corex boats? Thanks for sharing!

@@ChannelX24 Hi there's quite a few Corex /corruflite boats and designs out there including canoes and small motor boats. But the one that's closest to the image saved on my old phone is like a longer AquaNaught.

@@clivestainlesssteelwomble7665 Its a material with quite a lot of possibilities for small craft. The weight being so little I suppose is a big plus, and how easy it is to cut for manufacturing. I wonder if solid polypropylene sheet could be used in the same way? It wouldn't be as lightweight but incredibly strong and wear resistant. Thanks I've had a look at the AquaNaut.

@@ChannelX24 It comes in different thicknesses and grades.. 8 or 10mm Corex is tough .. the darker the colour the better the UV resistance ...it's even semi fire retardant. Cut it with fine saws or Stanley blades. The one awkward bit is sealing the eds of the flutes.. to stop them filling with water...but it can be done. Solid polyprop is quite heavy.. the same suppliers also make vinyl boards which has a gloss finish over a lower density core. The most common thickness for correx is 4-6mm single flute ..used for estate agent signs etc. the big stuff is usually double wall and some even has an Al foil skin but in and it's tough as and as much as 25mm thick . There's the problem of plastics though.. and costs... Some pallets use ply tops.. but it depends what you want or need to do. I got interested years ago wanting to make SPAD RC flyingboat models. Simple Plastic Aeroplane Design's.

@@clivestainlesssteelwomble7665 Definitely sounds like its a material with a lot of potential for small boat design. Big strength to weight ratio.

Solid foam is a good option as it cant flood if damaged. Closed cell foam needs to be used for marine applications as it won't absorb water. You'll want to separate the foam from the water somehow (prevent fish nibbling and erosion). Cladding with ply could be a good way of doing this. I've not had experience during poor mans fiberglass, but I've looked into it in the past. It will depend on how long you want the pontoon to last, and how harsh the environment is. Epoxy effectively makes your ply into plastic so if you want something to be very tough and last a long time its a good option. Cotton is cheap, fiberglass is fairly cheap and epoxy is expensive. Have you looked into HPDE plastic barrels and containers? These can often be bought for cheap and then lasted to a pontoon frame. You could fill these with closed cell foam for redundancy and they are very tough.

Sounds good, the stability from a catamaran setup is fantastic. I'd add some buoyancy bags or chambers in case of the hulls flooding.

Thats right they are several pieces laminated together. Each beam is composed of 8 pieces of wood. The core of the beam is 25×50mm pine stacked to a 100mm thickness then where it steps down 2 100mm pieces again on each end. I used microfiber strengthened epoxy to laminate the sections together and metal pins for alignment. Then again with epoxy and screws to laminate 9mm ply sheathing to each side of the beam. The ply sheathing is one continuous piece in the shape of the beam for each side.