I am getting the right radius for a NACA 0012 16" chord from one layer of 400 double bias. You should manage with 200 plain weave. Suggest you don't glass the interior until you are ready to close it up, then add a couple of extra layers to the nopse section and an inner skin to the core. I use 10mm foam glassed on the outside and it conforms to the aft sectionof said foil. Unless the ply is very thin, I would cut slits in it pre bending. A sheer web at max thickness (I have a shaft) gives the sheet something to bend around. Glass only ahead of the web. I totally screwed up my first one, should have the second attempt ready this week, will post some pics. If you really want to get stuck into it, let me know what is unclear in the above.
Hi,
I was wondering what the current "best practice" idea is for building a simple rudder (I need to build 2 for my plywood proa, from last year). I was considering trying to make it as one panel, with no core material at the leading edge and bending the fiberglass 180 degrees, but the practice piece I made seemed like that was too much of a bend for the fiberglass. It seemed like it wanted to delaminate, because the outer layers had to be longer than the inner layers to make the curve.My next idea was to build the rudder in two halves, using Derek Kelsall's deck edge radius type scheme and glue the 2 halves together, but I wasn't sure of being able to make a good bond on the inside of the curve.Finally, I guess I could just carve foam, and layup the fiberglass over it and then vacuum bag it.What is the current thinking? I would like something pretty simple, and it doesn't need to last long, but I would like to get it done soon so that I can try out the proa sailing this summer.Thanks,- Gardner