I was resealing the thru hull fittings on my boat the other day and things got a little messy and I didn't notice that I left behind a small palm print. What is the best way to remove 3M 4200 without damaging the gelcoat? Is there a chemical that is safe to use, or should I carefully try to wet sand the area? I tried the search engine and didn't get any hits, thanks in advance for any replies.

C4 or good amount of Dynamite... 3M makes softener/remover but costly I'd guess and probably have order it. At least it's not 5200 might try a razor?

I would try WD40 first.

Should just rub off with your fingers, with a little pressure.

If you have a multi tool with the scraper blade, it will take it off very easily in one piece with no damage to boat if you keep it flat

i use a razor blade/scrapper and acetone.

There is a spray called Unhesive that got my jackplate off and that was on with 5200. Glass shop said they would have to tear it off and repair the broken glass. The stuff works.

I may start with a little WD-40, I also read about Unibond Sealant Remover if I can find it. I'll check on the Unhesive too and see if anyone carries. It's a real thin spot so it's hard to get under it with a blade to try and pop it off, I haven't been able to get any good C4 in years, maybe I can use a little tannerite and hit it with the AR. Thanks again for the suggestions.

"I haven't been able to get any good C4 in years, maybe I can use a little tannerite and hit it with the AR."

the stuff can be unreal on how strong it is, good luck!