Gelcoat isn’t just for looks on your fiberglass car; it plays a crucial role in preventing hydrolysis and adds to the vehicle’s structural integrity. When deep scratches penetrate the gelcoat, they can expose the underlying laminate to moisture, leading to hydrolysis.
Understanding Gelcoat and Hydrolysis
Think of gelcoat as a dense protective layer. Its density makes it naturally resistant to hydrolysis, the process where water breaks down materials. A thicker gelcoat layer offers even greater defense. However, deep scratches compromise this barrier, making the fiberglass susceptible to water damage and hydrolysis, which weakens the material over time.
Why Filling Deep Scratches is Crucial
If you attempt to sand out deep scratches, you risk thinning the gelcoat too much. A thinner gelcoat provides less protection against hydrolysis. For fiberglass coated cars, especially in areas prone to scratches, it’s better to fill deep scratches with new gelcoat rather than sanding them away. This restores the protective layer and prevents water from reaching the fiberglass laminate.
For severely scratched areas, consider filling the scratches and even adding an extra layer of protection. Options include applying a 2k paint or an epoxy coat over the repaired gelcoat. The primary goal is to prevent water from breaching the gelcoat, as water is the catalyst for hydrolysis. By maintaining a robust gelcoat layer, you protect your fiberglass car from degradation and potential structural issues caused by deep scratches and water intrusion.
