Days 4-? were frustrating.
BIG MISTAKE #2: Bondo is a polyester epoxy and West Systems is something else. The Bondo started to eat away the foam, which required then even more filler to fix. Anywhere the West Systems epoxy was already placed, no problems, but bare foam was in trouble. More filling and sanding, filling and sanding...
Finally shaped to put a layer of fiberglass over the top. I hadn't fully thought through mistake #2, therefore didn't think about the polyester resin I was applying over the fiberglass... This proceeded to eat through the rest of the foam not protected by previous layers of epoxy.
So, in a tough decision I cut out the portions of glassed foam that had been eaten away and re-filled with the Bondo filler. Lots more sanding to smooth it out and another layer of glass over the top.
At this point you may have noticed that the hole in the trailing edge of the rudder was not accounted for... I hadn't completely forgotten about it, but didn't think it through previously. Using the measurements made at the beginning, I at least remembered where it was supposed to be, so I drilled a small hole all the way through, then used a large bit to make the hole in the foam/fiberglass much bigger. I used a plastic drinking straw to mark the hole (just shy of 1/4 inch) and filled around it with Marine-Tex. After setting, the straw was pulled out, the hole was widened to the 1/4 inch, but left an epoxy buffer to seal around it.
Is it just me, or does anyone else get a kick out of this?:
Now it was time to fair out what I had left and see how it all fit back together.
The blue paint is a Rustoleum metal primer/paint. I am waiting for some marine primer and bottom paint for the rudder, so I'm done for now. Goal is to see about fitting the whole boat in the garage and working on projects there, though I'm way behind my nonexistent schedule... I've got some concrete work, compression post, electric wiring, and a variety of other things I want to tackle before the spring.
Time will tell if this was worth it. I learned plenty by making mistakes so maybe this will help someone else out. At the end of the day I have a NACA-14 foiled rudder with PVC tops and bottoms and two layers of glass over an inordinate amount of body filler. The shape is close to the template, though slightly thicker than anticipated due to the layers of fiberglass. With bottom paint, I think it will look fine and we'll see how it works in a few months.
Hope this helps some others, I'm happy to make the mistakes for you. Some could have been prevented by actually reading the labels on the sides of the products...