Inside Gunwales
See Plan sheet 06/10
The inside gunwales consist of three pieces of wood 16mm x 35mm running the full length of the boat (so not worry if these are a few millimetres short at the ends. They will get covered up by the plywood brackets anyway and, unless you are a craftsman, dealing with all the angles and lengths can either be frustrating (or a challenge depending on your outlook!). Glue and screw (from the outside of the hull) the first strip in position and then you can glue the next two to the first using clamps. The screws can be removed when the glue is dry.
Make certain the two temporary frames are in the correct position or the topside measurements will not be within the allowed tolerance.
Mast Thwart
Cut the mast thwart bulkhead according to official plan sheet 06/10. Make up
an 18mm thick piece for the thwart by laminating some 6mm and 12mm ply
together (or use an "offcut" of 18mm). The thwart needs to fit tightly under the gunwales with generous
fillets of glue so that it remains in place. Refer to the plans for the
details.
After the glue has set measure and mark the centre of the mast hole (see Plan Sheet 03/10) and cut this to the appropriate size (see CR 3.2.2.13).