How to Fix Rotten Stringers on a 1988 Sea Ray Sundancer
- 1). Locate the four plywood stringers with a stud finder. The stringers run the length of the hull, one at each chine (where the side of the hull turns into the bottom) and another between each chine and the keel (at the center of the bottom). Work on one stringer at a time, marking the location with an indelible marker. Draw a line between the marks, outlining both sides of each stringer.
- 2). Drill a hole into the hull at each end of each stringer--one hole at the bow of the boat, one at the stern--with a hole saw the size of a reciprocating saw blade. Insert the saw through the holes and saw along the marker line, cutting a panel the size of the stringer out of the bottom of the boat. Replace each stringer completely before starting on the next.
- 3). Cut the stringer out of the hull from the outside, using any means necessary. Measure the size of the fiberglass pocket that enclosed the stringer. Cut a new stringer to fit. Replace the old stringer with a new one. Nail or screw the new stringer to the Sundancer's frames.
- 4). Drive screws though the panel into the frames to hold the panel in place. Use at least two screws per panel.
- 5). Spread a thick coat of marine epoxy resin along the sides or sides and ends of the panel you just reinstalled. Instruct your assistant to lay fiberglass cloth over the panel and work the fiberglass into the resin with a putty knife. Apply a second layer of resin and lay a second layer of fiberglass cloth over the first, working the cloth into the resin. Repeat until you build up at least five layers of fiberglass cloth and resin. Work in sections about 3 feet long along the full length of the panel.
- 6). Allow the resin to cure completely. Sand the resin down with a palm sander and 120-grit sandpaper until it's level with the hull surface. Switch to 220- or 320-grit sandpaper to polish the repair. Mix and apply gel coat to the repair. Allow the gel coat to dry completely. Paint and wax the repaired hull.
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