Following on from the rudder skeg, has to follow the rudder itself..........and what a whopper it is. No doubt made large to give better steerage as I don't suppose there was much engine steerage from the water jets themselves.
because it is so large, I decided to make it from birch faced ply for the inner section and mahogany faced water proof ply for the exterior. I also made it from four layers, the outside layers having the grain running vertically and made from 1.8mm ply. one inner layer of 2.0mm thickness had the grain running horizontal, and the final inner layer of 1.5mm ply with the grain running at 45degrees.
I did this in order for stability of the timber, because running the grains alternately, the rudder, as big as it is will not then have a tendency to twist or warp, even if it spends a great deal of time getting wet.........which I doubt will happen anyway. Sadly with my bad back and arthritis they seldom get their bums wet anymore.
you might notice from the first photo that on the rear edge of the rudder, the outer skin overlaps by around 10mm along its length. the other outer skin does also. this is to facilitate the square section brass tube that will be inserted into the trough, which then will be filed at sections to take the brackets that the solid brass bar that will run up through the square section, and through the holed in the brackets which will then be glued into the stern post..............making the whole rudder as one assembly..............if it confuses you, then it has certainly been a brain teaser to me, but all will be revealed once the rudder is glued together.
I used aliphatic waterproof glue and plenty of clamps to give even pressure all over whilst gluing up. I'll release it in a few hours once cured.