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  #1  
Old 07-10-2018, 09:10 PM
brucen20 brucen20 is offline
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Default Problem with Tacoma PM28 finish

Really can't say if my guitars' problem is the infamous Tacoma finish problem or not. A slight crack in the finish on the top waist area allowed air to seep between the wood and the finish. As the finish lifted, the crack lengthened and more air intruded. The finish is coming off in chunks now. Never saw anything quite like it. It is as if it never really adhered to the mahogany b&s at all. I'm thinking that with care and a little time it is going to be possible to lift all this strange finish off and replace it with something else. I'm thinking about french polish which seems laborious but relatively foolproof. I might also consider a matte finish if the wood wasn't so beautiful. So far the Sitka top is unaffected. I never have tried a similar project on a musical instrument before and never intend to sell this Tacoma. Anyone ever seen this issue or tried this particular fix?
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  #2  
Old 07-11-2018, 11:44 AM
Frank Ford Frank Ford is offline
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Most likely it's the finish lacking adhesion to the sealer coat, and it does sound just like the same problem we've seen so often. I have seen some where it was possible to pick off all the pieces neatly.

Shellac should adhere well, so French polishing is a perfectly reasonable choice. A very light scuff sanding would be a good idea.

Scuff sand, wipe on shellac and spray nitrocellulose lacquer to get a regular lacquer finish.

It's neither cheap nor easy to get a good refinishing, but it's absolutely possible.
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Frank Ford
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Old 07-13-2018, 09:05 AM
brucen20 brucen20 is offline
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Thank you, Frank Ford, for the encouragement. I have to try it because the present condition of the finish very annoying!
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  #4  
Old 08-10-2018, 12:54 AM
songofthewind songofthewind is offline
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Default Finish lifting

This sounds like the dreaded Tacoma finish problem.
They brushed on a sealer coat which was from a defective batch, and which did not cure.
It is very easy to remove the thick poly finish with judicious application of heat and the use of a palette knife.
However, you really need to get all of that primer off before you try to refinish.
I refinished my PK30 with Liberon Finishing Oil, which is actually a very thin varnish.
Allow good drying time between coats, or it can be a little sticky, but it offers reasonably good protection and looks good, gloss or matte.
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Old 08-25-2018, 06:00 PM
BillRomansky BillRomansky is offline
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You can always soak it with lacquer, build the lacquer up, and take a safety razor as a plane to bring down the lumps.
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