next I tidy up my frames and cut some holes. Often people think this is to lighten the board which it can do. But more important is to ensure air flow throughout the board. Because my boards are hollow, the air inside expands when it's hot and contracts when cold. Hence the need for a vent. I've also made a bottom for the board which as you see in the photos is like a sheet, glued and clamped and left for 24hrs. Then I attach the frame to the bottom.
The next part for me is to design what I'm after on the computer using the shaping program AKU shaper. I already have a bank of shapes that I use and will change to suit what I'm building. From AKU I then send the file to the program Hollow Wooden board maker, which converts the shape into ribs and spine. Then I print these out and stick them onto marine ply and cut out using a jig saw. I then clean them up with a planer and file. This is the point where I will put concaves or vee into the board.