larman
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Thicken Epoxy
- Thread starter larman
- Start date
The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
Cigatoo
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Sure. Just grind / sand 80 grit everything nice and clean beforehand. Enlarge the area a little so you can feather it. Wipe with acetone and apply the thickened epoxy
Last edited:
RT Firefly
Enigma
Greetings,
Mr. I. IF you're over-coating your repairs OR putting on multiple coats of epoxy be SURE to remove the amine blush.
https://epoxycraft.com/epoxy-basics/amine-blush-what-you-need-to-know/
Mr. I. IF you're over-coating your repairs OR putting on multiple coats of epoxy be SURE to remove the amine blush.
https://epoxycraft.com/epoxy-basics/amine-blush-what-you-need-to-know/
Comodave
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If the area is very deep you may have to do it in layers so you don’t get thermal runaway. As said above make sure in between layers to clean off the amine blush with a brush and fresh water. Then sand the previous layer to give it some tooth, wipe with acetone to clean it and lay on the next layer. I would use a structural filler for the first layers and finish up with a softer filler to be sanded smooth. But if it isn’t too deep you may be able to just do one layer.
I would sand the paint away from the damaged areas. You don’t want to (shouldn’t) apply over any bottom paint. You need to get the damaged area’s edges back to the white gelcoat. Use a large sanding block so the repairs are flat and fared into the original gelcoat. An easy way to check for flatness, use a flashlight in low light. You’ll see any imperfections if there are any. Good luck on your repairs.
Giggitoni
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Please forgive me because I know very little of such repairs. However, wouldn’t proper preparation and a layer or two of fiberglass work better?
Comodave
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It depends on how deep the area is. If it is very deep than I use layers of glass and then thickened epoxy for filler. I use a right angle drill with a 3” Roloc adapter on it to grind the glass. He will need to grind down to good solid glass and then assess what needs to be done.
STB
Guru
Epoxy is fine as one component of fiberglass reinforced thermoplastic as a structural material.
Epoxy is fine as an adhesive.
Epoxy is fine as a cosmetic fairing and filling material.
Unreinforced epoxy is not a structural material, except in very limited ways.
If you are thickening it with short, medium, or long strand glass fiber, it can form a reinforced thermoplastic for structural applications. But, the longer the strands, the more structural -- and the harder to work with.
Where the scrapes are just into filler, I'd happily clean them up, clean up around them, and make a nice epoxy repair.
Where the scrapes expose significant damaged or removed glass fiber, I'd want to clean up the whole area around it, shape it for a tapered repair, and build it back up with fiberglass, before using epoxy to fill any cosmetic defects, to hide the texture of the glass, and to fair. Layer the larger pieces of glass under the smaller ones as you build it up. This is because it gives you the most bond to the old material, and then everything builds back with a good foundation. Don't do more than ~4 layers at a time or it can get really hot, melt the old work, not cure properly, or worse. You don't want to cook it.
It is fine as a cosmetic filler.
Epoxy is fine as an adhesive.
Epoxy is fine as a cosmetic fairing and filling material.
Unreinforced epoxy is not a structural material, except in very limited ways.
If you are thickening it with short, medium, or long strand glass fiber, it can form a reinforced thermoplastic for structural applications. But, the longer the strands, the more structural -- and the harder to work with.
Where the scrapes are just into filler, I'd happily clean them up, clean up around them, and make a nice epoxy repair.
Where the scrapes expose significant damaged or removed glass fiber, I'd want to clean up the whole area around it, shape it for a tapered repair, and build it back up with fiberglass, before using epoxy to fill any cosmetic defects, to hide the texture of the glass, and to fair. Layer the larger pieces of glass under the smaller ones as you build it up. This is because it gives you the most bond to the old material, and then everything builds back with a good foundation. Don't do more than ~4 layers at a time or it can get really hot, melt the old work, not cure properly, or worse. You don't want to cook it.
It is fine as a cosmetic filler.
ronobrien
Guru
If they are deeper that would work. A product I have used which is great for finishing is Silver Tip Quick Fair. It is an epoxy and is very easy to work with. A lot easier to machine/sand than epoxy resin.
fgarriso
Guru
Slo-Mocean
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What caused that damage ? That bottom gouge looks rather deep .
AKDoug
Guru
I did that when I scraped a rock, found an amazing product called System Three Gelmagic, two part gel that changes color as you mix it and it doesn't sag or run so you don't need to thicken it will anything. Mixes to the consistency of smooth peanut butter, has a long shelf life. I just used it after over a year of storage to mount a backing plate for a new flanged ball valve and it set up perfectly.
