A lot depends on the level of cosmetic finish that you need for the repair and how your part was originally constructed

If it looks like fibreglass matting has been used as reinforcement on the rear, then there's a good chance that it might have been made with a surface coat of polyester gelcoat. It might be this surface that has developed the slight bubble you've seen?

If this is the case, you should be able to blend in your newly applied epoxy repair quite well and maybe the whole part might benefit from a good polish with a machine polisher and compound. This might restore a bit of shine if it's dulled over time but test out on a less conspicuous bit first if there's any uncertainty











 


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