Recently I made my first attempt to build the rudder blades for my ECO 6, and met with a big failure. Advice, comments, suggestions are invited before I make my second attempt. The photos show what happened. The ?Meranti is very stiff, almost brittle. ?It appears to me I put too much epoxy mix in the V. The building plan diagram for the ECO 6 specifies filling to ?a line drawn at 13mm from the leading edge. The directions call for the line to be drawn at 15mm. I was aiming for the 13mm line but I expect I added too much - it was difficult to tell. It was also difficult to keep two pieces of plywood so that they meet only on the corners - i expect the join looked more like the one in the left of my rough drawing. I am not sure how significant that might be. If that is critical, perhaps someone might suggest how to achieve that.
In one photo of the end of the blade, the epoxy appears to have failed. In my impatience, I tried bending things the morning after the pour and the epoxy was set but had not fully cured. I heard a loud crack and stopped bending and left it for 48 yours before trying again. I used a combination of ratchet straps and then clamps to close the V. Even with the trailing edges completely closed, there was still a large gap between one side of the blade and th 20X20mm spacer.. I left it over night like that to see if it would close any but it would not. To see what would happen I ?applied another clamp and of course, the plywood failed.
On my next attempt I will make the line much darker, and I will use a refillable calking cartridge (which I have and didn't think to use) to place the epoxy mix more carefully. A friend suggested that the V needs be closed some but I am not convinced that is the best solution. I look forward to hearing other's experience.
Rod McLaren
