Accidental damages to the gel-coat should therefore be repaired as soon as possible to prevent structural weakness sustained over time by moisture creeping into the fibreglass laminate.
It is easy to repair the gel-cot, and if you use the right procedures and materials, the repair will be impossible to detect afterwards.
You will need the following materials to repair your kayak:1. Acetone
2. Sanding block
3. Wet sandpaper of the following thicknesses: 400, 600, 800, 1000 and 1200. (If you are unsure, your local hardware store or marine supply store will be able to guide you.)
4. Thin brush
5. A sharp knife
6. Polishing paste (such as Autosol chrome polish)
7. White Gel-coat putty/filler (such as plastic padding)
- A small spatula
- Clean rags
- A bowl of water
- An hour of your time
Procedure
Clean the damged area with acetone on a clean rag. This will both clean and dry out the last moisture from the damaged area, and improves the conditions to attach the new gel-coat to the surface.
Mix the gel-coat according to the product instructions. On rule that applies to polyester products is that the more hardener is used the quicker it will harden. A normal ratio is 3%. Brush the gel-coat on the damaged area. Be sure to apply the gel-coat especially well to the edges of the damage.
When the gel-coat has hardened, it is time to polish the repaired area. Start out by using the No. 400 wet sanding paper on the sanding block. Use plenty of water when sanding and rinse repeatadly to prevent the sanding paper from clogging up. With the 400 paper you’ll sand away the surplus material and shape the right form. You will now know if you have used enough gel-coat to repair the damage. If nor you will have to dry out the area, clean it with acetone and start over. WARNING – the gel-coat is only 1-2mm thick on the kayak, so it is easy to sand through to the fibreglass if you are not careful.
Now that you’re finished with the sanding it is time to polish the area to it’s former glory. Use a polishing machine or brute handpower together with polishing paste. Wash and dry.
At this point the initial damage should be repaired and impossible to distinguish from the rest of the kayak.

