Sailboats utilize an underwater wing to prevent side slipping (literally being blown sideways) when sailing on a beam reach (perpendicular to the wind).
Small sailboats are typically given a centerboard and daggerboards. Larger and heavier boats are supplied with keels. My boat's keel is a retractable keel, providing a boat draft range of 9 in. to 4 ft. Made out of steel and with a large, bulbous ballast on the end, it pushes 350 lb.
Raising and lowering the keel is done via a wire rope connected to a ratchet winch in the cockpit. The wire crosses a standing block before being routed into the boat cabin and into the keel trunk.
The trunk houses the keel inside the boat and keeps it from view. Inside is a double tackle configuration, with the lower blocks attached to the keel wing via thick, stainless steel brackets.
Issue #1: Pulleys and cable replacement
The current 3/16 in. wire and 3 in. pulleys are rusting badly. I plan to replace all of these. The wire rope will be attached to an overhead bolt via a loop. (Point A in the picture).
I plan to use a thimble on the wire, but how should I reconnect the wire to make a loop? With a U-clamp or with a swage sleeve?
Issue #2: Splash-proof lubricant
The keel rests in wooden guides, located fore and after along the keel edge inside the trunk. Obviously this is a potential big source of friction.
The wood is currently rot free, likely due to the healthy quantity of yellow-brown and slightly sticky lubricating grease present in the grooves (point B in the picture).
I'd like to supplement or replace this lubricant with a splash-proof lubricant to help keep this area trouble-free--any recommendations?
Issue #3: Keel limiting mechanism
At the base of the keel trunk, there used to be a keel limiter bolt. Its job was to prevent the keel from extending below the boat (and thus becoming ineffective and potentially dangerous). It's former estimated location is point X in the second picture.
A previous owner removed this bolt, likely because it leaked somewhat. That owner also epoxied over this area and made marks along the wire rope to prevent extending the keel too far.
However, there was not a mechanical way to prevent the keel from dropping out below the boat, and I'd really like to implement one in case a friend is helping me do it one day.
Some ideas:
- Size the wire rope to the maximum extension of the keel. This would eliminate extra windings around the ratchet winch.
- Or install a sleeve on the wire rope that prevents a point in the wire from going through the first block, with the same purpose.
- Reinstall a limiter bolt. However, I don't really know what I'm drilling into here. All I have for reference is pictures on the internet.
- Install a wire rope leash. An extra line measured to size that prevents the keel from dropping too far. One click back on the ratchet winch would take the weight off the leash and back onto the pulleys.
This is the issue I need help with the most. How do I prevent the keel from extending beyond it's maximum 4 ft. extension?
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Sailboat Diaries: Keel Conundrums
Re: Sailboat Diaries: Keel Conundrums
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