Gelcoat repairs

Hi all-

So I bought a kayak trailer- I good idea for the most part so far, but with a few issues… one of which is the minor bounciness of the ride which is rubbing through my gelcoat! I have a glass boat with a nice white gelcoat and have always used a Thule Glide and Set setup on my roof, but’s it’s never constantly wiggled in there.

So I have this powdery white stuff on the rubber Set to Go saddles which once was my kayak. I believe it’s because the boat was a little dirty, and I think 300 miles of bouncing dirt between hard rubber and gelcoat - the gelcoat lost that one.

I since have bought some felt furniture sliders to cover the rubber with, since the rear felt covered pads have never made any problems, FWIW. I’m hoping for the best.

The damage is relatively thin, and I could live with it since it’s not to the glass. But I think I’d like to try to fix it.

My question is:

What must I do to get a low volume of gelcoat to stick in a low volume scuff? I haven’t tried yet but I think I understand that the curing process requires heat, and small repairs are tough. Should I try the styrene suggestion, and if so, where do I get that? The damage is too thick to sand away, and for that matter it’s too big to want a thin area that big, especially on a place it’s possible it would happen again.

I’m planning to use the Evercoat Gel-paste from West Marine, and I don’t know if they have “styrene” since I live a long way from the closest West Marine.

Thanks in advance!


I would say
If the glass is not showing just lightly sand if the gel is rough and buff the gel. It is not that easy to do shallow repairs on bigger areas with great results.


Greyhawk is right
The gelcoat paste you have will cure properly if applied to the outside of hull, but you’ll have to spread and sand it carefully to get it to blend in. Very thin repair are one place where liquid gelcoat is easier to work with than the paste. You can get “finish” gelcoat at West Marine and other suppliers. It’s designed to cure when exposed to air.

Heat is not necessary to cure gelcoat, but it speeds the curing process. You need to do the repair in a warm area (70-ish or higher) to get reasonable cure times. If need be, you can apply localized heat with a space heater or work light, if your work area is otherwise too cold.

Finish Gelcoat
Can I sand the finish variety just like the non-waxed type? (I think I saw it referred to as waxed and non waxed). Any best ideas for adhesion in the thinner spots, or just clean the heck out of it with degreaser/denatured alcohol/etc?

Thank you for your help!

Scuff it with 600 dry and lay it on with
the edge of a sheet of paper or cardboard. I like paper because it follows the contour more easily and leaves a thicker coat. If you are repairing on a radius it can get a little dicey. I sanded a 10"square area for spider cracks on a radius and ended up having to get a pro to finish it. A small flat area should be fine. A deep gouge is actually easier to repair than a wide shallow. Make sure a wet sand won’t fix it first, if you are through to the glass then its off to the gelcoat. Once hard, use 600 wet, 1200 wet, 1500 wet, 3m heavy duty compound, and finish with “finesse it” by 3m. The radius of a soft chine is a killer if the repair is larger. Good luck. Bill

Might want to change cradles also
I’ve been trailering my glass boat using Malone Autloader J-cradles since July. They have not done anything to the gel coat, maybe because they have rubber on the contact areas. I always rinse and wipe the cradles after each use, too, because we live on a dirt road and I want to get any grit off them. I also rinse and wipe the boats due to zebra mussel larvae threat.

The trailer bounces a little and the cradles flex–I know because when I look in the rearview mirror I can see the cradles flexing. Yet the gel coat is still glossy. The trailer suspension is a Torflex type, which is supposedly in between leaf springs and motorcycle coil springs in terms of stiffness.

Send my an email at and I’ll return the bell Canoe/Placid boatworks gel repair protocol.


Yes, all gelcoat can be sanded

– Last Updated: Oct-24-08 7:39 AM EST –

As moparharn said, you need to scuff sand the area after cleaning it with a good solvent like lacquer thinner. Personally, I'd use something coarser than 600 grit, more like 320. Regardless, his application technique sounds good. Just remember that you have to coat a larger area than the repair and wet sand it to feather in the edges and blend in the new gelcoat. Working with thin layers can be frustrating, as it's easy to sand off too much, requiring re-coating. It's a time-consuming process that can't be rushed if you want good results. Take your time, but be prepared to make mistakes, as it's part of the learning process.

Before you get into all this work, carefully assess the damage to the boat. If the gelcoat is just scuffed and it's not visibly thinner, I would just wet sand it with 600, 1200 & 1500 grit, then buff it out. Remember, this is the hull. It's going to get a lot of abuse and no one sees it when you're on the water. It doesn't need to have a perfect finish and trying to maintain one will drive you crazy, not to mention keeping you off the water constantly while you do repairs.

For pictures of the process, check out my Webshots albums at: