Sinking Feeling

 Besides the keel binding due to rust, I discovered a few other issues last season. Perhaps the most concerning was the leaking keel pivot bolt that could have sunk the boat! I believe there were a couple factors that contributed to this. First, the friction between the cast-iron keel and the stainless-steel pivot bolt was immense, despite having slathered the bolt in Lanocote before launching. This caused the bolt to rotate in the keel trunk periodically when raising or lowering the keel, thereby breaking the adhesion of the Life-Seal I added inside the cabin between the sides of the keel trunk and the bolt/washer combo. Second, I used flat neoprene sealing washers with flat fender washers. I was unable to find stainless-steel cone washers at the time. This likely resulted in the neoprene washers being squeezed outward from the bolt under compression, leading to leaks.

To remedy this, I first added the previously described bronze pivot bushing, reducing friction, still using Lanocote also. I also located EPDM bonded stainless steel sealing washers. They are slightly conical and all one piece, including extra EPDM in the center hole to seal well even under compression. Second, I decided to bond two 3" PVC drain clean-outs (i.e. standard plumbing fittings) around the bolts to encapsulate any leaks, even if the sealing washers don't work or the pivot bolt spins. Recalling that epoxy doesn't typically bond well to PVC, I did some reading in the West System literature, including this article: Bonding PVC Plastic with Epoxy. I opted to use their recommended G/Flex epoxy, thickened with some colloidal silica, forming fillets on both the inside and outside surfaces. I sanded, solvent-washed, and flame-oxidized the PVC as recommended also.

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