Gel Coating problems

motor dumb

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Jan 15, 2012
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Hey yall I have a problem. I put a new coat of gel coat on my boat and it doesn't seem to be setting up like it did the first time I did it. I think I know what the problem is but not for sure. The first time I did it it was a lot warmer outside (at least 80 degrees) this time it only got to about 70. I also question weather or not I put the exact amount of hardner in it. If I got off on the hardner ,will it still harden, or do I have to start over. I hope not it will probably be a mess. it seems to be working a little it is tacky after about 24 hours. But not for sure, any suggestions would be appreciated.
 

Bondo

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71,357
Re: Gel Coating problems

Hey yall I have a problem. I put a new coat of gel coat on my boat and it doesn't seem to be setting up like it did the first time I did it. I think I know what the problem is but not for sure. The first time I did it it was a lot warmer outside (at least 80 degrees) this time it only got to about 70. I also question weather or not I put the exact amount of hardner in it. If I got off on the hardner ,will it still harden, or do I have to start over. I hope not it will probably be a mess. it seems to be working a little it is tacky after about 24 hours. But not for sure, any suggestions would be appreciated.

Ayuh,.... Welcome Aboard,... Give it more time, 'n Heat if possible,....

I'll move this to the restoration, 'n repair forum for ya,...
 

Woodonglass

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Dec 29, 2009
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Re: Gel Coating problems

Yeah, Heat and time will be the solution. Also did you put wax in the final layer or spray it with PVA?
 

jbcurt00

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Re: Gel Coating problems

How long between the 2 times you applied gelcoat?
 

motor dumb

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Jan 15, 2012
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Re: Gel Coating problems

It has been a while about 2 years between coats. If it has wax in it can i still spray it with PVA.
 
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JASinIL2006

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Feb 10, 2012
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5,745
Re: Gel Coating problems

It's not the same batch of gel coat from two years ago, is it? I didn't think shelf life was that long...

Jim
 

motor dumb

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Jan 15, 2012
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Re: Gel Coating problems

No its a new batch, but i bought it about 1 year ago but was not opened until i used it this past weekend.
 
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jbcurt00

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Re: Gel Coating problems

Proper prep of the old cured gel, proper mixed gel w/ wax shouldn't need PVA to cure.

If the gel or MEKP is 2yrs old, its certainly possibly the problem.
 

Woodonglass

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Dec 29, 2009
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Re: Gel Coating problems

It depends on how it was stored. Was it in a cool dry climate or did it get hot in the summer time out in the garage? If so, there's a good chance it might have gone bad. What kind of prep did you do on the Old Gel before applying the new? No PVA needed with Waxed GelCoat but You can't apply another coat over the top of the previous coat once it's cured unless you prep it first.
 

Georgesalmon

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Apr 14, 2012
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Re: Gel Coating problems

JMHO, but I hate to say that it probably won't cure completely. It will get stiff and tacky with time and heat but that's just the solvent evaporating (styrene). Mix up a another small bit with proper catalyst and see what happens. The standard test is usually a 100gram mass with 1.8% cat at 70F to get the gel time that was designed in when it was made. Make sure you mix it up good before and after adding MEKP.
 

motor dumb

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Re: Gel Coating problems

All i did to prep it was just wash the boat. If I have to remove and start over how do i remove bad stuff and what should i do to prep before attempting to do it again
 

Woodonglass

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Re: Gel Coating problems

Prepping for gelcoat is not that much different than prepping for paint. You must wash, de-grease, sand, fill scratches and gouges, sand, fair, wash, de-grease, wash down with acetone, and now You're ready for Gelcoat.
 

Georgesalmon

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Re: Gel Coating problems

Remove by scraping and I'd use acetone soaked rags but that not the safest thing to do. However you remove it its a big mess. A good sanding with 100 grit is all you need to prep.
 

motor dumb

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Jan 15, 2012
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Re: Gel Coating problems

I appriciate all the help i am going to give it another try this weekend will let yall know how it turns out. Once again I want to thank you.

John
 
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