The hull on the port side had two historical gel coat repairs. These two repairs did not match the color of the original gel coat, and were not sanded nor buffed. Another gel coat repair located toward the bow and on the port side was performed by me, and although the gel coat was sanded smooth, the color was much whiter than the original hull color.
After viewing a "how to match gel coat color" video, I decided to spray gel coat on the previous repairs in order to better match the gel coat to the color of the hull. With my color kit of of black, yellow, brown I made several colored gel coat test samples on a freshly sanded area of the hull -- sand an area of the hull to remove the oxidation so a palette is available for gel coat color samples.
After 90 minutes of various amounts of yellow and white, I had the color close to perfect. Using a Preval mini sprayer mixed with gel coat, styrene thinner, and gel coat hardener, I sprayed the gel coat in small even motions. The gel coat sort of spattered out of the nozzle and created and orange peel texture. Thinning the gel coat more would have helped the viscosity of the gel coat when spraying from a tiny nozzle (Preval) but may have caused problems during the curing process of the gel coat.
The color of the newly sprayed gel coat was a better match to the hull, yet, much sanding would be required to smooth the gel and complete the job.
The picture above with this post shows the white gel coat patched before the new sprayed gel coat. After the job has been sanded and buffed, a post will be made showing the complete gel coat repair.
Considerations - Investigate a gravity feed gel coat gun. A gun with a larger nozzle may make spraying gel coat efficient, albeit a compressor will also be required.
