During haul out, I noticed a quarter size hole in luffalee’s rudder apx. 2” behind rudder post on the top edge. There was a small amount of rust stained water just below the surface of the hole, so I drilled some exploratory holes around the area. Of course, the rudder was wet and there was standing water in the leading and trailing top corners. The center and bottom of the rudder seemed dry, but I wasn’t excited about having standing water in the rudder, so I had the boat lifted and took the rudder home to explore.
My initial idea was to cut open the areas where the standing water was, remove and replace saturated foam, and reuse the removed skin. However, when I applied air to the hole at the bottom of the rudder a small amount of water came out so I decided to open the whole thing. Surprisingly, the skin was extremely well bonded to the foam core and it took almost 30 minutes of careful prying to get it off. The problem was immediately clear, there were large voids in the top corners of the rudder so when the rudder was holed (could have happened when my motor fell of the back and was hanging on by the battery cable, but that’s a whole different story) water filled up the void. On the positive side, the rudder post and structure looks reusable and 90% of the foam is in great shape.
I have a few questions on the rebuild.
- I’ve heard 16 – 20 lb foam is ideal for this process, but the foam used seems to be much less dense. Possibly 4-8 lb. I’m thinking it would be best to use the same density foam. Anyone have any ideas on what Ericson / Foss used in the original?
- I can find the foam on USComposites.com, but shipping is expensive and they seem to take a while to fill orders. Does anyone know where I can get foam in the Seattle Everett area?
- Should I reuse the old skin, bonded with thickened epoxy, and taped with tapered seems or reskin the rudder with 1708 biaxial and epoxy? I have access to a vacuum pump to ensure good adhesion, but I’m a little concerned about the strength of a taped seem.
- The rudder post and joint is in great shape and I can’t see any sign of leaking or stress cracking. However, I know this is the source of most leaks so should I break a good seal and re-build it or keep a good thing going?