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Here are some steps to consider when dropping a keel for repairs.
1. Haul out and cradle. Put a jack under the keel to ease it down later or else use screw jacks on the cradle pads to raise the boat. For boats longer than 27 feet, or when the cradle is unsuitable, book a Travelift or crane. You may need to devise a way to separate the keel and hull.
2. Rent or borrow tools. You'll need extra deep sockets, a heavy drive bar, an extra-long lever arm (a pipe will do) and a long extension to reach into the bilge. You may also need a variety of wedges and a sledge hammer, plus glass tools for grinding, filling, fairing, etc. Professional yards rarely lend tools.
3. Undo keel nuts. Use a thread lubricant to help prevent stainless-on-stainless galling (binding and seizing).
4. Expose the joint. If needed, grind away fillers or fiberglass to expose the keel-hull joint.
5. Lifting. Lift the boat (or drop the keel) so that the full weight of the keel is suspended by 1/4-inch or so, then take a break. If the keel doesn't drop on its own (most won't), carefully drive wedges in between the keel and the hull at the joint. Lift the keel or lower the hull and repeat until 5cm to 7.6cm (2" to 3") of bolts are exposed.
6. Assess. Inspect bolts carefully to assess any corrosion damage.
7. Remove. To remove the keel, install braces to support the keel in an upright position. Lift the boat, or lower the keel the rest of the way.
8. Repair. Proceed with the bolt repair or replacement as required.
9. Clean. Clean mating surfaces on keel and hull with a mini grinder.
10. Start re-attachment. Reposition keel under hull and mate bolts to holes in hull.
11. Apply sealant. Apply thick bead of sealant around each bolt and hole only – don't cover mating surfaces with sealant as its flexibility makes the keel wiggle too much.
12. Apply adheasive. Mix up epoxy resin thickened with cabosil and chopped fiber to a thick paste. Apply liberally to top of keel.
13. Re-attach. Immediately join keel and hull together and torque into place using a staggered tightening pattern. Recradle if needed.
14. Clean again. Before epoxy fully cures, remove excess that has squeezed out. Make sure air temps are warm enough for epoxy to cure, otherwise set up heat lamps.
15. Finish work. Fill and fair the repair area, repaint and launch. Check for leaks. If it leaks, see Step 1 (we're not kidding). If not, go sailing in heavy air. Check again for leaks.
1. Haul out and cradle. Put a jack under the keel to ease it down later or else use screw jacks on the cradle pads to raise the boat. For boats longer than 27 feet, or when the cradle is unsuitable, book a Travelift or crane. You may need to devise a way to separate the keel and hull.
2. Rent or borrow tools. You'll need extra deep sockets, a heavy drive bar, an extra-long lever arm (a pipe will do) and a long extension to reach into the bilge. You may also need a variety of wedges and a sledge hammer, plus glass tools for grinding, filling, fairing, etc. Professional yards rarely lend tools.
3. Undo keel nuts. Use a thread lubricant to help prevent stainless-on-stainless galling (binding and seizing).
4. Expose the joint. If needed, grind away fillers or fiberglass to expose the keel-hull joint.
5. Lifting. Lift the boat (or drop the keel) so that the full weight of the keel is suspended by 1/4-inch or so, then take a break. If the keel doesn't drop on its own (most won't), carefully drive wedges in between the keel and the hull at the joint. Lift the keel or lower the hull and repeat until 5cm to 7.6cm (2" to 3") of bolts are exposed.
6. Assess. Inspect bolts carefully to assess any corrosion damage.
7. Remove. To remove the keel, install braces to support the keel in an upright position. Lift the boat, or lower the keel the rest of the way.
8. Repair. Proceed with the bolt repair or replacement as required.
9. Clean. Clean mating surfaces on keel and hull with a mini grinder.
10. Start re-attachment. Reposition keel under hull and mate bolts to holes in hull.
11. Apply sealant. Apply thick bead of sealant around each bolt and hole only – don't cover mating surfaces with sealant as its flexibility makes the keel wiggle too much.
12. Apply adheasive. Mix up epoxy resin thickened with cabosil and chopped fiber to a thick paste. Apply liberally to top of keel.
13. Re-attach. Immediately join keel and hull together and torque into place using a staggered tightening pattern. Recradle if needed.
14. Clean again. Before epoxy fully cures, remove excess that has squeezed out. Make sure air temps are warm enough for epoxy to cure, otherwise set up heat lamps.
15. Finish work. Fill and fair the repair area, repaint and launch. Check for leaks. If it leaks, see Step 1 (we're not kidding). If not, go sailing in heavy air. Check again for leaks.
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