Structural Repairs
Damage to the hardtop such as cracks or holes that pass completely through the thickness of the fiberglass laminate and into the foam core are known as structural damage. This type of damage can affect the strength and structural soundness of the laminate. All structural repairs require the use of fiberglass patches to provide the mechanical strength needed to keep the repair structurally and visually intact during normal usage. The patch also provides the required foundation to build and form the exterior surface to match the original contours. The following is recommended for these types of repairs:
IMPORTANT:
Any damage that fractures the hardtop through both layers of laminate and foam core substructure is to be considered non-repairable structural damage and the hardtop should be replaced. Any damage that deforms the roll bar of steel reinforcements in the hardtop, even though there appears to be no major fractures in the laminate, should be considered non-repairable damage and the hardtop should be replaced.
1. Sand off finish from around the damaged area and inspect for cracks in the laminate.
2. Remove all broken and fractured laminate and grind a "V" around the hole to provide maximum adhesion.
3. Cut fiberglass patches to fit the opening.
4. Clean area to be repaired with Sikkens M-600 or equivalent.
IMPORTANT:
Cleanliness is very important. Be sure that the repair area is clean and free from dust and debris.
5. Mix polyester resin and hardener at ratio recommend by manufacturer.
IMPORTANT:
Remember, cleanliness is important. Mix the polyester in a clean container. Do NOT use waxed cups for mixing. Be sure to close resin and hardener after use.
6. Coat opening with resin/hardener mixture and apply fiberglass patch. Using a 25 mm (1 inch) brush saturated with resin/hardener mixture, pack fiberglass firmly into opening. Make sure you have thoroughly wetted the fiberglass patch.
7. Repeat step 6 until the damaged area is built up to approximately 0.8 mm (1/32 inch) below the original contour of the surface.
8. Finish the build up with Sikkens Polystop LP or equivalent.
9. Apply heat to repair area. Heat lamps are recommended to be used at least 300 mm (12 inches) away from the repair. Allow at least one hour of curing time. If heat lamp is unavailable, allow to cure at room temperature of 21 to 24 Celsius (70 to 75 Fahrenheit) for eight to ten hours.
10. Finish the repair by grinding, sanding and cleaning in the usual manner.
11. It is recommended that the entire hardtop be repainted. See Dealer Service Bulletin No. 89-292-10 for paint specification and application.
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