The rudder on my 1983 Mason 43 had some hollow sounding spots and some evidence of delam in the lower edge. My instincts tell me that the areas I am talking about are small enough relative to the overall area of the rudder that nothing done would probobly be OK, but thats not really my style.
I drilled holes and ground (grinded?) away the crappy parts. Now in some areas the foam core seems to have vaporized. Also there appears to be cells within the rudder such that any water intrusion - only found on the lower edge in the rear - seems to stay local. I built clever little clam shell from garbage that have allowed me to let them stay open in the cool winter air without me wondering if water is getting in.
My questions and pardon if they are stupid. For the voids, can I use the foam stuff one finds in 'home improvement ' stores before doing the glass work. Research indicates the stuff does not absorb water. Is it better to use thickened epoxy? Straight epoxy? From there I am using standard techniques, but read somwhere that the binders in mat are not epoxysoluble. Is it OK just to alternate the layup with different weight rovings, alternating bias?
None of the repairs are near the top where the shaft enters the rudder, but one is near the bottom where her lower pintle exits. Near, not on. No signs of stress fractures exist anywhere. First all paint was removed and the gel coat sanded.
Any other thoughts or tips are appreciated.