Late 60's Goya finish question

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Late 60's Goya finish question

Postby Steven Wilson » Thu Apr 19, 2012 6:04 pm

Hello I have an old Goya nylon string that the finish is doing that orange peel thing. It's only on the neck and head stock. What type of finish is this likely to be(I think nitro) and is there a fix? I'm only familiar working with lacquer and urathane. The owner commented that the guitar had seen a lot of camp fires so I suspect bug spray.
Thanks
Steven
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Re: Late 60's Goya finish question

Postby Michael Lewis » Fri Apr 20, 2012 1:11 am

Steven, can you put some pics up? It's hard to tell from here.
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Re: Late 60's Goya finish question

Postby Steven Wilson » Fri Apr 20, 2012 9:20 am

Here's athe headstock
Attachments
orngepeel 001.jpg
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Re: Late 60's Goya finish question

Postby Michael Lewis » Sun Apr 22, 2012 1:53 am

This looks like blistering from what I can decipher. Excessive heat is most likely the cause and it could be any finish. If it is not blistering then it could be oil base varnish 'crawling'. This can be caused by heat or resins in some woods. Some rosewoods can reject finish in some areas, the finish never gets hard.

More inspection is indicated.
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Re: Late 60's Goya finish question

Postby Steven Wilson » Tue Apr 24, 2012 9:51 pm

Thanks Michael
I don't think it's heat because it's only on the neck. My main concern was finish type as I am doing some repairs on the body. I believe it's lacquer, a little lacquer thinner softened the finish.
Thanks again
Steven
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Re: Late 60's Goya finish question

Postby John Hamlett » Tue Apr 24, 2012 10:55 pm

Hard to tell from the picture, but it might be plasticizer migration, sometimes called a "strap burn" from vinyl or other plastic in contact with the finish, usually in the case. Could be bug spray, could be... many things.
If that's what it is, there fix can vary with how bad the damage is, how deep into the finish, and so forth. I've had some that had so much plasticizer throughout the lacquer, that I could scrape the gummy finish off to the wood with my thumb nail. The only repair was "R&R" (removal and replacement, in other words, refinish). If it's only superficial, it can be level sanded and buffed. Usually, it's somewhere in between.
Could be something else, though...
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Re: Late 60's Goya finish question

Postby Michael Lewis » Wed Apr 25, 2012 12:44 am

Steven, you didn't say if the damaged finish is soft or hard. That information could point to a better answer.
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Re: Late 60's Goya finish question

Postby Clay Schaeffer » Wed Apr 25, 2012 7:10 am

If the finish is lacquer, and is hard rather than gummy, you may be able to reamalgamate the finish with lacquer thinner or butyl cellosolve. Clean the finish of waxes and polishes with naphta before using the solvents.
Shellac also reacts to lacquer thinner as well as its more usual solvent, alcohol. Lacquer is less reactive to alcohol, so testing with alcohol may help you determine which it is. Shellac can be reamalgamated using alcohol and top coated with more shellac.
I have a Goya classical from the 70's but I'm not sure what the finish is.
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Re: Late 60's Goya finish question

Postby Steven Wilson » Wed Apr 25, 2012 10:04 am

Thanks for the replies
The finish is hard. I will test a little alcohol and see.
Thanks
Steven
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Location: Eastern Shore Maryland


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