How to Rebuild Fiberglass Wood Stringers
- 1). Use the sawzall and sander to remove the damaged areas of the stringer that need to be rebuilt, such as where rot has occurred. Measure the area removed and cut a piece of wood to replace the damaged part of the stringer. Glue it into place with construction adhesive and let dry.
- 2). Sand the area adjoining the portion that is to be rebuilt. Also use the sander to slightly round any hard edges of the new wood. Use the shop vac to remove as much of the sawdust debris as possible, then follow-up with the tack cloth on all surfaces to remove the last of the fine sawdust.
- 3). Cut several pieces of the fiberglass matte to cover the area you are rebuilding, so you have these on hand while rebuilding the stringer. Mix the fiberglass resin and the hardener In the disposable mixing container, being sure to follow the manufacturer's directions. Typically, the more hardener used, the quicker the resin hardens.
- 4). Brush an even coat of resin on the area being rebuilt and the area immediately adjoining it. Lay the fiberglass matte in the wet resin and apply a second layer of resin with the paint brush. Use the fiberglass roller to ensure the matte is wetted thoroughly and to work out all air bubbles.
- 5). Wait for the first layer of fiberglass to begin to cure and become tacky. Repeat the process of laying fiberglass for a second layer, then a third. Let the resin cure completely.
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