cracked finish

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Mike Sandor
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cracked finish

Post by Mike Sandor »

I have a guitar that has been finished approx. two years. I have recently noticed that when looking at a angle, there are numerous cracks.
Is it possible to lightly sand the entire surface and respray a very thin mix in effort to melt into the previous finish? Or should I just sand the entire guitar and refinish.
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Steve Senseney
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Re: cracked finish

Post by Steve Senseney »

My guess is that the guitar got cold, and the finish cracked as it shrank more than the wood underneath.

It would be important to know what finish was used.

I

Mike Sandor
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Location: wisconsin

Re: cracked finish

Post by Mike Sandor »

Steve, that is what happened, the finish is lacquer.

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Barry Daniels
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Re: cracked finish

Post by Barry Daniels »

What kind and brand of lacquer?
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Mike Sandor
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Re: cracked finish

Post by Mike Sandor »

Seagrave Nitrocellulose Spraying Lacquer from Stew Mac.

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Barry Daniels
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Re: cracked finish

Post by Barry Daniels »

In order to re-amalgamate the finish cracks, you will need something more than a thin coat of lacquer. Some folks use butylcellosolve. I have used straight lacquer thinner but it may take several passes to completely remelt the finish. And you need to do this on horizontal surfaces only because when remelted, the finish can sag.
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Mike Sandor
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Re: cracked finish

Post by Mike Sandor »

Barry,
I appreciate the help. Do you think I need to scuff the surface before spraying?

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Barry Daniels
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Re: cracked finish

Post by Barry Daniels »

No, that won't help.
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Barry Daniels
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Re: cracked finish

Post by Barry Daniels »

Spray a few light coats of lacquer thinner and wait a couple of minutes observing the surface closely. You will see some healing of the cracks but probably not all the way to the wood unless your finish is really thin. Spray another coat and then observe for a couple of minutes. Repeat until the cracks disappear. The goal is to get the cracks healed with the minimum amount of thinner possible. Let the surface cure for an hour minimum, then turn the guitar and do another surface. Hopefully, the sides don't need this cause they will be a big challenge to prevent sags.
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Mike Sandor
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Location: wisconsin

Re: cracked finish

Post by Mike Sandor »

Great, thanks again for the help. The sides look fine, will let you know how it turns out.

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Mark Swanson
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Re: cracked finish

Post by Mark Swanson »

Those are just some little old finish cracks. It happens on lots of vintage instruments, and isn't really a big deal. You can of course do as you want, but to me they don't look bad and if it were mine I'd just leave it alone. All old Gibsons are covered with these cracks.
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Mark Wybierala
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Re: cracked finish

Post by Mark Wybierala »

People pay good money for age related cracks.

Michael Lewis
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Re: cracked finish

Post by Michael Lewis »

I think your finish is probably too thick. A thinner film is less prone to check like that.

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