How to Repair Fiberglass Steps
- 1). Put on your respirator and grind the repair area using a dye grinder. To use the grinder you will need a air compressor and hose, which you can find in different sizes at your local hardware store. If the repair is a crack or fracture, you will need to grind directly on the crack three-quarters of the way through the fiberglass, forming a grove. Taper the walls of the grove as much as possible. The more gradual the walls of the grove are, the stronger the bond will be. If you have a hole, you will need to cover the hole using aluminum tape. The hole will need something flat and hard placed behind it in order to prevent the aluminum tape from sinking in while adding the new fiberglass.
- 2). Clean the area using a rag and acetone. Remove any dust or grease that remains on the repair. This will help assure a strong bond.
- 3). Mix the filler and the hardener together as directed on the containers. The filler is very thick, so to assure the hardener is mixed properly, you will need to use your hands. Wear rubber gloves when handling fiberglass because the hardener will burn your skin. When the filler is one solid color, it is ready to apply.
- 4). Pack the repair with the filler, using your hands. Smooth the filler by using a putty knife. You may need to repeat this process more than once to assure a level surface. Let it cure until the filler is hard and cool to the touch.
- 5). Sand the hardened filler smooth using coarse sandpaper. If the filler is not flat and level with the surrounding surface, repeat Steps 3 and 4 until you have a satisfactory repair.
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