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  #1  
Old 05-22-2019, 07:49 AM
jbbgibson jbbgibson is offline
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Default Finish Repair Advice

I have a new build on an Indian Rosewood L-00. The finish is nitro gloss leveled and brought up to a semi gloss using micro mesh stopping at 3200. While inspecting after completion I noticed some thin areas of lacquer on the binding. To these I applied additional layers of nitro brushing on with cotton swabs and re-sanding.

My problem is, while applying nitro to the binding, an errant drop landed on the back of the guitar. I did not notice this for about 5 minutes and it had partially dried by that point. I decided it was best to leave it and deal with it when it had dried completely. After letting it sit a couple days I re-sanded with micro mesh again up to 3200. The finish came out just fine except for a small fish eye where the drop landed and likely melted into the layers below. It can only be seen in the right light reflection so I can't get good pics. You cannot feel it. Unfortunately, its all I see when I look at the guitar.

I am looking for advice on how to deal with this. If left to my own devices, I would think my options are:

1. Brush more lacquer over the spot with a cotton swab hoping it would melt into the spot and re-sand again.

2. Re-sand with micro mesh 2400 and lower the finish to satin instead of the current semi gloss hoping it will be unnoticeable at that point.

3. Tape off the area and completely sand the spot gone and spot refinish the area.

Any help and advice anyone experienced with this is more than welcome!

Thanks in advance!

JohnnyG
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Old 05-22-2019, 08:31 AM
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Frank Ford Frank Ford is offline
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A drop fill, or in thie case an extra drop of will melt into the previous lacquer coats, causinhg the finish to swell a bit there. If you let it dry and level it within a week, there's a good chance that the melted area underneath will shrink back to reveal a shallow crater.

Drop fills are most successful if allowed to harden for a month rather than a few days. . .
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Old 05-22-2019, 09:30 AM
redir redir is offline
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Don't ya just hate that? My advise would be to show it to a friend and see if they even notice it. I don't think I've built a guitar yet, and I'm working on #65 now, that I am the only one who sees a flaw in.

I don't think sanding through the spot is a good idea, you might just make it worse. If you do dig out the spot then maybe consider drop filling with CA. Then you don't have to wait another month.
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Old 05-22-2019, 03:58 PM
jbbgibson jbbgibson is offline
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Thanks for the input. I will go with Mr. Fordís advice and put another drop on the location and let it cure for the month.

I saw a Dan Erlewine video using your razor blade trick to scrape down CA used to drop fill. Is that appropriate here as well for initial leveling? Or should I just sand?
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Old 05-22-2019, 06:23 PM
mirwa mirwa is offline
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Personally, i scrape any drip fills down to height, then i wet sand smooth.

Scraping removes IMO less of the original paint.

You can also go to a paint shop and get a nib remover, these are a perfectly polished 1 inch approx square block of stainless steel, designed for knocking of paint runs when doing car work, when i am doing the back or top of a guitar i use one of these for any drip fills, sides I use a scraper.

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Old 05-23-2019, 09:10 AM
redir redir is offline
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A razor blade is a good tool for getting the leveling real close. I usually round off the corners and even turn the edge like you would sharpen a scraper. Use a thin tape like the kind of tape you wrap Xmas gifts with and tape off the edge of the blade on each side so that only the middle of the blade, wide enough for the drip or run, is exposed. The tape will act as a stop so basically you will scrape the drip down to the thickness of the tape.

Another trick to finish that off is to press a small strip of sandpaper right on top of the drip you want to flatten with the tip of your finger and pull the sand paper out while maintaining pressure. Repeat till level then polish out the surrounding area.
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