Hawse pipe plugs
The J/42 has two slots on the forward edge of the anchor locker cover, intended for leading a rode through on its way over the side. Unfortunately, they can also let a lot of water into the anchor locker when taking waves over the bow. Because there's only one drain for the locker and it's a small one, the water goes back out only very slowly. Take enough water over the bow, and you can fill the locker up, which happened to Bill & Kathy on their boat Jarana on passage to San Francisco. The water ended up coming through some forgotten holes in the forward bulkhead and onto their berth!
I decided to plug the holes with removable plugs. Here's what I came up with.
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The cover of the anchor locker with the plugs in place.
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Underneath of the cover.
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Detail of the plugs. They were made by sanding down 5/4" teak to the appropriate shapes, then laminating the pieces together with thickened epoxy.