How to Fix This Gelcoat or Paint Blemish?

[MHBsailor]

Wondering if this blotched area in the middle just below the teak coaming is gelcoat (or paint?) that came off of the substrate? Not sure if Cape Dory used gelcoat or paint in that area. I'd like to refinish it so that it has the same finish as the rest of the area around it - any suggestions what to use (e.g., spray gelcoat with a Preval sprayer or spray paint, etc.?). If it's gelcoat, I recall there is a place near Seattle that still has the original Cape Dory colors, but don't recall the name. Thanks! JD

[John Stone]

Wondering if this blotched area in the middle just below the teak coaming is gelcoat (or paint?) that came off of the substrate? Not sure if Cape Dory used gelcoat or paint in that area. I'd like to refinish it so that it has the same finish as the rest of the area around it - any suggestions what to use (e.g., spray gelcoat with a Preval sprayer or spray paint, etc.?). If it's gelcoat, I recall there is a place near Seattle that still has the original Cape Dory colors, but don't recall the name. Thanks! JD

That sure looks like paint in the photo but I can’t tell For sure just looking st it. I can only talk about my own boat. It was originally all gelcoat. But these boats are getting pretty old and many have been painted as has the Far Reach. All I can tell you is anything can be repaired and most repairs are not that difficult if you do your homework and take your time.

[MHBsailor]

Thanks John! I'm thinking it must be gelcoat, since that's the only small area with this issue and it doesn't look like it was painted anywhere. Can gelcoat be rolled on, or should it be sprayed to get that nice smooth finish, or is that obtained by sanding with a fine grit paper afterwards? JD

[John Stone]

Thanks John! I'm thinking it must be gelcoat, since that's the only small area with this issue and it doesn't look like it was painted anywhere. Can gelcoat be rolled on, or should it be sprayed to get that nice smooth finish, or is that obtained by sanding with a fine grit paper afterwards? JD

I don’t have any experience with gelcoat. I have seen it done in a video with a prevail sprayer with the area masked off then buffered to eliminate the edge. They mixed and matched the gel coat right there. Sorry I can’t be of more help. I’m sure there are a couple experts on the forum. You could post a question separately with subject asking for gelcoat tips. YouTube might provide the answer. Can’t be that hard.

[Steve Laume]

I am definitely not an expert with gel coat.

I have tried using it once, when I decided to spray it onto my fiberglass dodger project. I ordered it from the place in Washington state where I was not guaranteed a perfect match but figured it would be closer than what I could come up with. Premixed color with hardener was over $100 a quart. The mixing ratios are such that I used syringes to measure out the materials. It only takes a tiny bit of hardener and you don't get extra nor do you want too much in the mix. Once combined, the working time is only a few minutes. It will take a few coats as they want a thin film and it must be applied to an uncured surface or you need to sand again. The number that loomed large on my mind, was that I only had 20 minutes, before my rather nice spray gun became a rock, that no solvent would restore to a usable condition. I used a regular high pressure spray gun, which was probably the wrong tool for the job. I had a large area to cover which made it more difficult. The quart I ordered would not have been nearly enough to complete my project. The finished coating is going to be heavier than paint. The finished coating will also need to be sanded and polished without cutting through it. I started on the inside of my dodger and managed to get a few coats on the thing with two spray guns involved. I was able to save both of them. The finish came out horrible. Thin in some spots and thick enough to run in others. This was not my first go round with a spray gun but this stuff was difficult to apply. When it dried, I decided I was not going to attempt to finish my project with gel coat. Some of it didn't cure properly so it could be removed with solvent and the rest was sanded off. I went with paint and it came out pretty well with much less stress and it was a whole lot cheaper.

If you have a small area and can have them mix some as a gel and it would probably work out fine. Most gel coated surfaces you see are the result of being sprayed into a polished mold. This eliminates many of the issues that result from a mix that will cure in the air. The stuff I got had a wax additive that floats to the surface and allows it to cure. I might have had better results if I got it without the additive and then sprayed another coat of oxygen blocker on top. I was not about to find out.

Gel coat can be that hard, Steve.

[Frenchy]

I think that looks like paint, too. Usually, if gelcoat is stripped away, fiberglass
strands in the mat beneath will be visible. But in your photo, the area looks uniform
under the coating.
Gelcoat repair isn't hard. If you're interested, contact Gel Coat Products in Seattle.
Ask them to mix the Cape Dory white with Duratec, 50-50, adding extra color to the mix
because of the Duratec dilution. The Duratec will thin the gelcoat enough to spray well and
also air-inhibit the mix so it'll cure. For a small job, the Preval sprayer works well. I'd get
rid of the glass jar, though, and insert the suction tube into a paper cup (non-waxed). That
way, you can tilt the sprayer better for horizontal surfaces.
Other tips: Mix very,very well after catalyzing 2% with MEKP. I also spray the gel coat
after it has set up a bit with PVA (an air-inhibiting agent). That's just in case it decides to
not cure. You'll have to wet-sand with 400 and 800 grits, then compound.