No estoy de acuerdo.Algunos gelcoat necesitan ser tapados .
Unas instrucciones en ingles
http://www.roguepaddler.com/gelcoat.htm
Let the gelcoat cure for at least one full hour, preferably two. Better yet, keep an eye on the gelcoat residue in your mixing tray. When it hardens thoroughly, it's probably a safe bet that your repair job has hardened thoroughly as well. If you have any doubts about whether the repaired gelcoat is fully cured, wait longer. Never begin sanding the repaired area unless you are entirely certain the repair has had sufficient time to cure. On the other hand, if five hours later the repair still isn't dry, you probably didn't add enough liquid hardener to cure the paste completely, and now you have a disastrous bit of clean-up and re-repairing to do.
IMPORTANT: Some polyester gelcoat pastes must be sealed off from the air in order to cure fully. Refer to the manufacturer's instructions on the gelcoat can. If sealing is required, use acetate film or wax paper.