Gelcoat repair issues

[cdlong]

I have started gelcoat repairs on SeaCracker and am having issues. i started by opening the cracks with a church key, but that wasn't working out. I went to a dremel with various shaped stones and am taking the cracks & nicks down to fiberglass. I'm using Evercoat Marine match & patch. My issues are: pin holes in the gelcoat after sanding with 220 grit. I assume I'll have to add anothe layer and repeat the sanding process? I have several areas where I'l sanded thru to the fiberglass upon sandind with the 220 grit? I'm not so much worried about the color as I know a really good match will come with continued repairs. 1st batch was a little to reddish, second batch was closer. My sandpaper ranges from 80 to 800 grit & I'm using rubbing compound & Mother's carnauba wax. I tried several marine waxes, but Mother's has the best shine.

[cdlong]

More pictures. I haven't finished opening up the last 2 pictures yet. Just giving you an idea of what I'm doing. Any advise, different tools, etc. will be greatly appreciated!

[Bikecop1]

Following with interest.

[cdlong]

Update, It took 3 batches to get the color very close. Now I have to grind out all the previous repairs and redo them. Buy the large tubes of tint, they are much easier to get uniform drops from. I save the cardboard I mix the hardner into the gelcoat on to check the color. Only do one repair until you get the color right. I have purchased a palm polisher from Harbor Freight to compound, polish & wax the top sides of the cuddy. I also am using an electric palm sander for the 500 & 800 grit wet/ dry paper. Yes, I have a GFI, but I'm using a hand spray bottle. I use the Mouse & triangle sanders dry, then wet sand by hand with 220 or 320 depending how thick I put the gelcoat on, I realy like the Evercoat gelcoat, it doesn't run. There were 3 holes in the last picture which was the 3rd batch of gelcoat. They need need a cover, (thin) coat, then final sanding using 500 wet/dry, then 800. Fololowed by the rubbing & polishing compounds, then wax.

[cdlong]

Found a guy in VA Beach. He told me the "burn thru" is actually the primer that was applied to the fiberglass before the gelcoat was shot. Dark primer helped show the coverage depth of the gelcoat while it was being applied.

My son, the painter, said Dad toss the plastic spreaders and get some flex puddy knives. I got a 1 1/2 & 3 inch knife. Seems to be helping a lot getting the air out of the gelcoat. I'm going to try a foam brush to apply the gelcoat over the spots where the primer shows thru. If this doesn't work, I'll have some Rustoleum paint tinted and apply it with a foam brush, Then wet sand just enough to get it smooth.

[Wildfire]

I am not familiar with the Evercoat Patch system you are using but it sounds like it is thickened gel coat. If it is then the pin holes you are getting is from the gassing produced by the heat created by a relatively thick liquid. We do these repairs all the time. This is our method. Use regular white gel coat
(not thickened with no wax added). You can use the tints you already have to get your color match. Once you have your match you mix your gel coat one to one ratio with Duratec High Gloss Additive. Both the gel coat and Duratec can be purchased at any good fiberglass supplier. Thicken the gel coat into a paste by adding some cabosil., add your hardener and apply like body filler. It will shrink a little. After sanding with 100 grit repeat the process. If you are satisfied with the finish, final sand with 220 grit going out a few inches past your repair. Harbor Freight sells a little 4 oz gravity feed paint gun for about 13 dollars on sale. If you plan on continuing to do your own touch up work this gun is the best 13 bucks you'll ever spend. Mix another batch of gel coat and Duratec the same ratio. If your base repairs are a pretty close color match then you can reduce your gel coat with lacquer thinner another 10%, ( thinner also cuts down the hiding ability of the gel coat) add your MEKP and paint over your repairs out to the edge of where you sanded. Get rid of the excess gel coat and put some more lacquer thinner in the gun. Spray a little out to clear most of the remaining gel coat from the gun, then spray over the outer overspray ring to help melt it in and reduce the amount of sanding later. After curing sand the remaining overspray down with 400 and then 800 grit and finally with 1200 for light colors, 1500 for darker. Buff out with the compound of your choice. We use 3M Perfect-it extra cut, it is a bit pricey and only available at automotive paint suppliers. Because of the line edge on most gel repairs, unless you get a perfect color match you will always be able to see the repair. By spraying your final coat even slight mismatches will usually blend in enough so that the casual observer won't see it.
Good luck

[cdlong]

Thank you Wildfire. I'll consider changing my method.

[cdlong]

After many disappointments, here's what I've learned: open cracks with a dremel tool and V shaped stones. ( I went down to the fiberglass). Bevel the edges. Sand with 60 grit dry paper. Vacuum dust from in & around repair area. Wipe in one direction with acetone. Keep the rag clean. Tape repair area, (I kept mine a small as possible). Use gel coat with wax in it & be sure to use the correct amount of hardner, ie: Evercoat One Step. Spread with West Epoxy stir sticks, try to keep area smooth & over fill the crack, it will shrink, up to 25%. When cured, use sanders only if you have to. I used 180 grit dry then moved to 320 wet then 500 wet then 800 wet. I used a spray bottle of water with dish soap in it. Helps keep the paper from loading up with gel coat. For the follow steps, I purchased 2 buffers from Harbor Freight, 1-6 inch & 1- 10 inch, ( I'm wet sanding the entire boat with 800 and performing the following); (purchase rubbing & polishing compounds in bottles). I purchased hook & Loop pads, (rubbing compound, polishing compound & wax), from HF and placed male Velcro on the pads that were on the buffers. I also purchased bonnets for the buffers but found placing a microfiber rag under the buffer saved a lot of time. I did " 2 coats" of rubbing then polishing then wax. Once I get some done correctly, I'll post pics. Like I said, until today it's been very nerve racking.

[kmoose]

Originally Posted by Wildfire

I am not familiar with the Evercoat Patch system you are using but it sounds like it is thickened gel coat. If it is then the pin holes you are getting is from the gassing produced by the heat created by a relatively thick liquid. We do these repairs all the time. This is our method. Use regular white gel coat
(not thickened with no wax added). You can use the tints you already have to get your color match. Once you have your match you mix your gel coat one to one ratio with Duratec High Gloss Additive. Both the gel coat and Duratec can be purchased at any good fiberglass supplier. Thicken the gel coat into a paste by adding some cabosil., add your hardener and apply like body filler. It will shrink a little. After sanding with 100 grit repeat the process. If you are satisfied with the finish, final sand with 220 grit going out a few inches past your repair. Harbor Freight sells a little 4 oz gravity feed paint gun for about 13 dollars on sale. If you plan on continuing to do your own touch up work this gun is the best 13 bucks you'll ever spend. Mix another batch of gel coat and Duratec the same ratio. If your base repairs are a pretty close color match then you can reduce your gel coat with lacquer thinner another 10%, ( thinner also cuts down the hiding ability of the gel coat) add your MEKP and paint over your repairs out to the edge of where you sanded. Get rid of the excess gel coat and put some more lacquer thinner in the gun. Spray a little out to clear most of the remaining gel coat from the gun, then spray over the outer overspray ring to help melt it in and reduce the amount of sanding later. After curing sand the remaining overspray down with 400 and then 800 grit and finally with 1200 for light colors, 1500 for darker. Buff out with the compound of your choice. We use 3M Perfect-it extra cut, it is a bit pricey and only available at automotive paint suppliers. Because of the line edge on most gel repairs, unless you get a perfect color match you will always be able to see the repair. By spraying your final coat even slight mismatches will usually blend in enough so that the casual observer won't see it.
Good luck

I was just introduced to Duratec recently and have been mixing it with my deck and gunwale gelcoat that I am rolling on. I mix it 3 parts gelcoat and 1 part Duratec. All I can say is wow? No more wax or surfacing agents to mix that are hit and miss at best, the stuff is amazing. I did try going 50/50 but it was too thin and required multiple coats so I changed the ratio. For those who are going with a non-sprayed or sprayed gelcoat finish.... Duratec is the shizit. Gloss and unbelievably durable finish. I did a small area on my rebuild and decided to do the whole cap with it.

[cdlong]

Thank you kmoose. I have purchased the spray gun that Wildfire referred to. I have added Evercoat Wax-Sol to my gel coat starting yesterday & I'm pleased with the results. Wish I had know about waxing agents from the git-go. But hopefully this thread will help any other newbie's wanting to do their own gel goat repairs.