There is a sister boat to mine. The owner reported that the rudder design he felt was poor and needed improvoing. The rudder that comes with the boat is a plain flat one.
A bit of reserach came up with several designs that are better and give more turn for your buck. In the end I decided to go for a type know as a Schilling, or Fishtail rudder. It has several other names but these are the most common. Having read a great deal about them and the maths involed I came up with my design.
Here is the whole rudder in parts form.
Once all marked up I tack welded the parts together so I could drill them all together.
The small parts are the attachment parts
Then the drilling. The large holes are to take the rudder stock pole which is 50mm.
Once drilled I tack welded the parts together. When making things it like this it's best to tack it all just in case it need altering.
Once its all together its fully welded.
Once the supporting ribs are in place the outer skin needs attaching. This a 4mm sheet of steel and its best forced over the ribs cold to prevent any distortion that heat might cause. The flow over the rudder would be affected by this. This is a slow and gentle process using g-clamps to ease it into place.
1st side done
This is the finished rudder
The two smaller parts earlier will be used later on the rudder pivots and will bolt on tho the top and bottom of this part. This is to enable the rudder to be removed if the the drive shaft needs drawing out. More on that soon.
Also on the go at them moment is the construction of the pram hood. Again more on this as there is something to show.