Repairing gel coat damage

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Repairing gel coat damage

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quinn	q quinn posted 7 Years Ago HOT Topic Details
q Group: Forum Members Posts: 155, Visits: 992	So I layed up another helicopter canopy, this time with frekote instead of pva. Came out beautiful, perfect gloss right out of the mold, but it took a little peice of the gel coat with it. It was a piece of the corner where it goes to the flange. About 10mm long, 2mm wide, not very big. Can I repair this? I used polyester tooling gel coat for finished mold surface. Should I just try to fill it in with the same stuff? It's pretty runny but I might be able to use some tape as a dam to hold it in place. Is this likely to work, or will I just lose it again? I suppose another option is to just fill in the corner with wax the next time I use it. Not a heavily used mold. Might do a few more canopies in it.
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quinn	q quinn posted 7 Years Ago HOT Post Details
q Group: Forum Members Posts: 155, Visits: 992	+x quinn - 11/6/2018 5:22:33 PM So I layed up another helicopter canopy, this time with frekote instead of pva. Came out beautiful, perfect gloss right out of the mold, but it took a little peice of the gel coat with it. It was a piece of the corner where it goes to the flange. About 10mm long, 2mm wide, not very big. Can I repair this? I used polyester tooling gel coat for finished mold surface. Should I just try to fill it in with the same stuff? It's pretty runny but I might be able to use some tape as a dam to hold it in place. Is this likely to work, or will I just lose it again? I suppose another option is to just fill in the corner with wax the next time I use it. Not a heavily used mold. Might do a few more canopies in it. Here's the canopy i pulled out. Very happy with the finish. Never should have bothered with pva.
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Warren (Staff)	Warren (Staff) posted 7 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	For a rarely used mould you could "cheat" and just use a bit of filleting wax especially if the area is very fiddly to work in for the repair. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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quinn	q quinn posted 7 Years Ago HOT Post Details
q Group: Forum Members Posts: 155, Visits: 992	+x Warren (Staff) - 11/7/2018 9:29:50 AM For a rarely used mould you could "cheat" and just use a bit of filleting wax especially if the area is very fiddly to work in for the repair. Sounds good. Probably will just do the wax for now unless I end up doing a large run. So if I did decide to do a more permanent repair, is just filling it in with same polyester gel coat the way to go? Or would something else like epoxy be better? I could probably also drill some tiny holes into the damaged area so it grabs on better.
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Hanaldo	Hanaldo posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Nah for a permanent repair just use the same tooling gelcoat, you just need to add wax-in-styrene solution so that the gelcoat cures hard rather than tacky. Drilling holes wont be necessary, just scuff the damaged area and clean it really well, perhaps score it with a knife if you're really worried about it.
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oekmont	oekmont posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	You can use epoxy, too. I did with some of my earlier tools, wich were made quite bad, and got damaged from time to time. The epoxy repairs never got damaged again, while the polyester repairs were just as good as the original gelcoat. But this was more of an demoulding issue. Usually, the original gelcoat should perform just fine.
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quinn	q quinn posted 7 Years Ago HOT Post Details
q Group: Forum Members Posts: 155, Visits: 992	+x oekmont - 11/8/2018 3:04:35 AM You can use epoxy, too. I did with some of my earlier tools, wich were made quite bad, and got damaged from time to time. The epoxy repairs never got damaged again, while the polyester repairs were just as good as the original gelcoat. But this was more of an demoulding issue. Usually, the original gelcoat should perform just fine. I'm guessing it stuck right there because I was being very careful to not roll over the flange corner of mold when sanding and polishing it, so I probably had a spot that was hit with heavier grit and then not fully sanded out with finer grit and polish. Next time I'll just use the frekote on plug for making molds so they don't need sanded afterwards. I originally used pva, so the finish on them wasn't perfect without sanding and polishing. Learning as I go. Would have saved a lot of time and money if I bought chemical release in the first place for both mold layup and part layup.
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