The router bit slipped a bit last week so adding more material at trailing edge. Should be able to glass the entire profile by this weekend.
October 30:
The rudder is developing. It took some time to layout and decide what balance could be achieved while housing the stock and keeping an angle similar to what is used with modern FFs.
Goal:
1. 15-30% balance by area.
2. Rudder stock angle from vertical 6-30 degree.
3. Rudder center of pressure centered on stock (by area).
Final: 15.4%, 14 degree from vertical, centered by area
The 97/2 plan profile of the rudder shows the airfoil normal to the leading edge of the rudder which is 43 degrees from vertical. The first method was to stack the profiles with wood blocks and shape it down to the profiles. I started with a naca 0011 foil which closely matches the plan profile but in the orientation this would develop an ambiguous profile wrt. to actual water flow. Re-mapping the profile in the direction of flow then plotting the resultant points for a 'normal to leading edge' orientation gave a new profile matched to another naca profile. Oversize patterns were cut and will be used to rough in the shape with a router suspended across the profiles. Next step is finish internal shaft and torque pin assembly followed with epoxy glue up of ll parts.
A first layer of epoxy was used on the keel after giving it a better support rack. Bad news is the keel has a 25 mm twist in it placing the end point of the fin off center laterally. Will compensate with some shaping and the final mounting hole pattern to backbone.
