I did not measure the position of the mid seat forward frame from the edge of the ply sheet. I butted two sheets of ply together, drew both the side panels and then marked the position of all the frames using the origin point (the front lower edge of the side panel) and the cumulative dimensions for each frame position as shown on the plans. This could account for some of the difference, while the obvious difference in the size of the butt blocks could account for the rest. (My plans definitely give "6mm x 254mm" dimensions for both side and bottom butt blocks in notes 1 & 2).Steve_MA wrote:My plans show the "mid seat fwd" frame to be 14 3/8" from the edge of the ply. If your ply is longer than 8', then it could be that your plans show the mid seat fwd frame close to the edge.
I'm not sure I understand Jeff's point about the metric size ply resulting in a longer boat - the ply I used was metric (2400mm x 1200mm) but since the measurements are taken direct from the plans to mark out the sides and frames, I can't see why the difference in material size should affect the size of the boat. The LOA of my boat is spot on the stated 4.25 (14ft).