During school holidays whilst Jake is down we are slowly building him and Dennis another dinghy each, only this time we are trying ply walls to see if light ply will create a lighter boat, not that the original is too heavy, as it is lighter than an equivalent rigid inflatable but solid duflex is way over engineered for the role it will have.
Last holidays we cut out the 4 bulkheads (2 for each boat) and some of the ply hull panels, yesterday we cut the bulkhead slots in the upright hull walls, the front bulkhead at 90 degrees the rear bulkhead at about 105 degrees (or 75 degrees depending on what side you are measuring from horizontal) to accommodate the usual 15 degree transom lean.
Today we started gluing the hull sides to the bulkheads to form the framework of the boat. Because we are using 4mm ply we also glued triangle shaped moulded timber bracing in each 90deg join to increase the surface area being glued and to hold the joins at 90degrees a little better. We only put these on joins on the inside of the hulls so that they will end up invisible (except perhaps inside a compartment). Outside we will cove and glass as we will need to glass the entire outside of the boat. We will also cove and tape the inside of the joins a glass any compartments inside but otherwise we will probably only resin coat the inside of the hulls.
Tomorrow we should be able to get the next hull panels onto the glued dingy and to glue the other dingy, we ran out of time this afternoon before getting the second set glued together. And of course I also still have to cove, tape and bog the glass on the starboard underside wing to hull joins.