Alligator'd gel coat

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Alligator'd gel coat

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AlpineCoupe	A AlpineCoupe posted 5 Years Ago HOT Topic Details
A Group: Forum Members Posts: 45, Visits: 2.1K	Was starting a mold today and got terrible alligatoring when I applied the second coat of gel coat. Is this only caused because I applied the second coat too soon? Or could there have been other factors causing this mess? Sorry the image is inverted, I'll fix it when I'm on a computer.
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AlpineCoupe	A AlpineCoupe posted 5 Years Ago HOT Post Details
A Group: Forum Members Posts: 45, Visits: 2.1K	+x oekmont - 6/5/2020 4:12:19 PM Aligartoring is a tricky beast. Sometimes it is hard to say why it happened. But there are some things that provoke it certainly: -Undercured gel coat -badly mixed gelcoat (uncured patches) -to thin gelcoat (a second layer doesn't help here, because it is styrene based itself. It has to be a thick enough first layer) -heavy brush lines From your pictures I get the feeling that your initial layer was very thin. My initial layer was pretty thin, and I was brushing it on. And I may not have waited long enough. Lots of possiblites. Lots to learn about this composite making. ButBut at least I'm still learning with every mistake!
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beliblisk	b beliblisk posted 5 Years Ago HOT Post Details
b Group: Forum Members Posts: 53, Visits: 2.8K	When i apply gelcoat i do it really thin on first brush up just to make sure i cover everything and then make another pass adding to normal thickness (probably close to 1mm).Second aplication is in thickness the same as firts. This way i never had any problems so far. Good luck Edited 5 Years Ago by beliblisk
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	+x beliblisk - 6/14/2020 6:56:59 PM When i apply gelcoat i do it really thin on first brush up just to make sure i cover everything and then make another pass adding to normal thickness (probably close to 1mm).Second aplication is in thickness the same as firts. This way i never had any problems so far. Good luck without letting it cure in between, correct? This is what I do as well as it takes advantage of the thixotropic properties of the gelcoat - thin when brushing, thick when left to sit. Brush it on so that everything is covered. By the time everything is covered, the gelcoat you've brushed on already has returned to its thickest state and you can brush over the top of it and disturb it less, allowing you to build thickness easier than if you tried to go straight to full thickness. But don't let it cure in between that first thing coat and the second thin coat, it is all done in one application.
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beliblisk	b beliblisk posted 5 Years Ago HOT Post Details
b Group: Forum Members Posts: 53, Visits: 2.8K	Correct. Just thin film followed right away with thicker second application (after about 2h folowed by "true" second layer).
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