Today I finally finished the rudder and installed the ram.
I had to modify the rudder fixing as my original idea to keep it concealed turned out to be very difficult to fit and remove the rudder. I wanted to fit it and remove it to be sure it could be done. Whilst it could be done it was very fiddly, so in the end I filled the tapped holes and re-dilled so that the bolts are accessible from the outside. Much easier, but not as pretty, but it will be under water so hopefully I won't see it that often.
As this is a Shilling type rudder its main advantage is that it will operate at angles over 35º to give better stearing especially at low speeds. The rudder arm supplied was calculated to move through 35º each way with a pre-drilled pivot point at 140mm but by re-drilling the pivot point to 104mm an angle of 50º each way was achieved.
This shows why I created the extra borrowed space
I'm glad that's done now it was pretty heavy work in an awkward space both inside the boat and outside.
The whole assembly moves very smoothly and freely. The bottom bearing is a simple steel on steel cup and plug set up and the top bearing is a self aligning pillow block bearing.
I now consider myself an expert on the construction and installation of a Schilling type rudder. I just hope it works as well as they are said to in this article.