Before I start fixing the plywood skin to the hull I am completing all the blocking that goes from under the keel frames to the plywood inside face. Each layer of blocking can be fitted and pressed into place in a bed of epoxy resin like a tile in a mosaic. Once all the blocks are in place the surface will be planed so that the plywood can be glued direct to the underside of the frame. The central layer of the blocking has only to resist the shear stress in bending and as it is on the neutral axis this is where 30 mm square access holes are located to carry all the water services and bilge pump plumbing. The bottom most layer of blocking is against the hull and is continuous except for the limber holes needed against the keel and stringers. Against the keel directly above the limber holes the frame section is 110 mm wide, 80 mm deep and encased in 2 mm thick high strength epoxy glass so it is a very impressive structure. Two stingers run through the blocking area on each side so there are between 8 and 12 blocks per layer for each of the seven frames. It is quiet time consuming to shape the blocks to transition smoothly from the 80 mm wide sections to the 110 mm wide section between the keel and king plank but a good smooth transition is needed so that the glass cladding is well bedded down for maximum strength. I have calculated that in the keel frames and blocking there is 224 individual pieces varying from metre long 80 mm wide by 6 mm deep layers in the frames to tiny pieces with two 45 degree angles. As a result of this time consuming task progress looks slow but it will pay dividend minimising the time for completion after the hull is turned. If I have counted correctly I have just 28 little pieces to cut and fit before I can start fairing the section in preparation for the skin.

Near side frame with 30 mm access holes through the neutral axis and far side frame with blocking spanning the access holes

Near side frame with 30 mm access holes through the neutral axis and far side frame with the extra layer of blocking spanning the access holes

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