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PostPosted: Sat Nov 06, 2021 7:13 am 
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Brazilian Rosewood
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I recently refinished a gold top Les Paul.
Just so everybody knows I finished hundreds and hundreds of guitars in my life and never had this problem.
So as you could see in the photo when I put tape on the finish and pulled it off the clear layer separated from the gold.
I prepared the word in the normal way send it out to 220 then sprayed on stew Mac gold out of a rattle can because I really couldn’t find it and paint form do you wanna let that dry and then sprayed six or eight coats of clear mohawk nitro over it let it dry for two weeks and then buffed it.
When the tape came up there was gold on the back of the tape so it didn’tSeparate between the clear and the gold actually it was the gold it failed
Before I refinish this again anybody have any suggestions?


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PostPosted: Sat Nov 06, 2021 7:15 am 
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Brazilian Rosewood
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PostPosted: Sat Nov 06, 2021 7:19 am 
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Brazilian Rosewood
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Also, as I scrape off the finish with a razor blade and a scraper it comes off way too easily so something is woefully wrong here.


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PostPosted: Sat Nov 06, 2021 10:38 am 
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How long was the tape on the guitar?
And were the finishes fresh?

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PostPosted: Sat Nov 06, 2021 12:33 pm 
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Brazilian Rosewood
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Chris Pile wrote:
How long was the tape on the guitar?
And were the finishes fresh?


The tape was on the guitar for an hour- and the finish was a month cured....


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PostPosted: Sat Nov 06, 2021 1:06 pm 
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Sounds like one of your finishes is the culprit.

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PostPosted: Sat Nov 06, 2021 2:47 pm 
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Brazilian Rosewood
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So it seems then it's an adhesion problem between the gold and the prepped surface. I wonder if some sort of sealer would help. How did you strip the finish?


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PostPosted: Sat Nov 06, 2021 7:45 pm 
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Brazilian Rosewood
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I scraped and sanded it off, no chemicals were used.


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PostPosted: Sat Nov 06, 2021 7:46 pm 
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Brazilian Rosewood
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jfmckenna wrote:
So it seems then it's an adhesion problem between the gold and the prepped surface. I wonder if some sort of sealer would help. How did you strip the finish?

Actually not only did the gold not stick properly to the wood when the tape came off there was gold on the back of the tape and gold still left on the guitar


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PostPosted: Sun Nov 07, 2021 8:24 am 
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Brazilian Rosewood
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Weird! It's almost like the top coat nitro layers melted in and the gold stirred up to the top. Perhaps more top coats would help that but that doesn't solve the problem with the adhesion to wood. I wish I could help but I cannot. Maybe strip down again and use a vinyl sealer or shellac over the wood before gold? Then perhaps even a sealer over the gold?


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PostPosted: Sun Nov 07, 2021 11:36 am 
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Koa
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I might not be following you, but the Stewmac site requires a specific sealer to spray over the gold lacquer. I do not see that in your post. You might also look into other brands of gold spray cans and see if they have the same solvent base as your problem one.


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PostPosted: Sun Nov 07, 2021 4:01 pm 
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Brazilian Rosewood
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wbergman wrote:
I might not be following you, but the Stewmac site requires a specific sealer to spray over the gold lacquer. I do not see that in your post. You might also look into other brands of gold spray cans and see if they have the same solvent base as your problem one.



I read it and they are saying to seal the wood -not between the gold and the clear.

I guess what I am looking for is someone who has successfully done gold top finishes.....


I routinely spray clear nitro over all different colors-opaque,transparent and semi-transparent with no problems which leads me to believe it is a compatibility problem with stew macs gold and the Mohawk nitro.

Therefore I am very hesitant to do it again

After all doesn't the saying go "the definition of insanity is doing the same thing over and over again expecting different results".....


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PostPosted: Sun Nov 07, 2021 6:36 pm 
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Have you tried contacting StewMac customer service? They sell the gold, so they might have some insight as to what could have gone wrong.


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PostPosted: Sun Nov 07, 2021 6:41 pm 
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Koa
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what sticks out to me in your story is the tape...the tape with the gold on it...to me this means the metallic gold paint didn't bond to itself (gold on tape, gold still on guitar)

this is interesting...perhaps, for whatever reason, the paint got on without enough solvents/clear? perhaps you didn't shake the can well enough (solids like color and flake fall to the bottom and would be sprayed out first methinks)?

just an idea perhaps with no merit

perhaps the issue is with the mohawk product not being as intended for use with stewmac's product and that would be rectified by using a stewmac clear


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PostPosted: Sun Nov 07, 2021 10:00 pm 
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Koa
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I don’t know if this is relevant to your case: 3M blue tape and nitro lacquer are incompatible. The blue tape will destroy totally cured lacquer even decades old. There is a warning somewhere on the tape label, maybe inside the core, about that. Usually, the green tape is okay.


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PostPosted: Mon Nov 08, 2021 12:02 pm 
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Koa
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Gracey for rattle can metallic finishes... we never saw any issues with their metallics, etc., although found that none of the rattle can packaged finishes replicated a true gold top finish. Clean the spray cap with acetone before and after every use, and agitate on a near-continuous basis. Gracey's Lake Placid Bluewas the only rattle-can that looked anything like the original Fender finish... I have a Tele body that I refinished in that color and may even see assembly at some point in the future.

An hour may be too long for 3M 2090 blue tape on fresh lacquer...for large area masks, we used low tack signmaker's tape (the white tape SM sells) over-coated with multi-surface blue tape. No issues. For fine masking and around hard line edges, we used Tamiya's 1/4" modelmaker's masking tape has just the right stretch and stick to allow masking of fresh lacquer without issue.

https://www.1bossco.com/products/copy-o ... -aprox-3-8

For gold tops, we used a dedicated spray gun from Harbor Freight with lacquer and metallic material (Crescent #255 or #256...both were used by Gibson at one time or another), and much more true-to-original than any of the rattle cans (although Gracey comes the closest). Meticulous prep and constant agitation required, but that work allows the finish to be laid down in multiple, thin coats without excessive build.

DO NOT shoot metallics in a gun that you want to shoot clears through...the HF jam gun is perfectly adequate for the job, and cleans out/up well even without a gun cleaner.

Finally, all of the Gibsons I saw which were true gold tops (not finished with that terrible synthetic color they were spraying for a few years) had scraped bindings...some even have some sliver of raw wood showing. Even with a less-than-perfect scrape on the bindings, you will likely be no worse off than the typical factory gold top from back in the day.

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