I can chime in here a bit. My
Scamp was in a wreck with PO. I immediately noticed gelcoat cracking when I bought from him, but overall repair was done at
Scamp, and knowing gelcoat can flex differently than FG, I figured it was residual stress from accident.
Now, two and a half years into owning trailer, I notice a definite yellowing/demarcation line on the roof. Which made me realize Scamp might have glassed in the repair, but they sure as heck used
paint too.
I've used Tolleys in cracked areas, haven't noticed any yellowing but my work is only a couple years old. All I have to offer here is my opinion, and I know my trailer was painted now due to the yellowing.
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