I have decided not to add 4 "sisters to the keel bolts in my Islander 28. I discovered the condition of the stub is sound. What I thought was the surface of the lead keel was a 1/2" steel plate. No lead is visible as per this post. My mistake. I do not like the condition of the exposed bolts. They ring true. The threads above the nuts are rusted to the point that they could not be engaged by the nuts if I backed them off. There is no leak associated with the keel. A visible seam is present but no latent wetness after hauling.
What worries me now is the amount and location (above the steel plate) of sealant visible in the bilge. IS THAT NORMAL? There is copious "sealant" around the perimeter of the stub. I would expect sealant would be used to bed and attach the lead. Why would it be above a steel plate that is part of the stub? I was planning to eliminate the original knot meter's thru hull that was moved by a PO from the side of the keel to a spot just above the turn of the bilge. It has a plug living there now. Considering the glass work involved with that and the anxiety surrounding the condition of the original bolts I decided to spend a week and lay up enough new glass structure to support a sister. I have the tools and experience to do the modifications to the hull. What I don't have is any experience with keel bolts!
Now I am deciding on the material for the new bolts. Any suggestions? SS seems logical but it will be encapsulated inside the keel. I am thinking of 1.25" or a little larger steel. Since I will be building the bilge beds for these new bolts I can raise them a bit higher that the originals to keep them out of any bilge water. The originals are steel and have lasted in terrible conditions since 1977.
I have a good laminate schedule including Kevlar but wonder if I should build in a steel shoe at each new bolt location and how far it should extend laterally?
I expect that when all the glass work is complete I will have covered the inner surface of the keel completely. I have to decide how to treat the existing bolts. I am thinking that a good wire brushing and then just work the new laminate around them can't hurt.
To keep the work area free of styrene I will be using System Three laminating epoxy resin. I plan to drill the holes in the lead before doing the glass work. I have practiced drilling into lead. That can be tricky and I welcome your suggestions. I will plug the holes with a piece of wood for the glass work and remove it when I am ready to install the bolts.
I will alternate sides for cutting the slots into the keel for the lower nuts and washers.
All comments are most welcome.