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Removing bad refinish without affecting original lacquer
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Sat Oct 28, 2017 6:56 am    Post subject: Removing bad refinish without affecting original lacquer Reply with quote

Hi,

New member here. I have a 1957 Silvertone 1303 U2 that I bought used when I was a kid. It came with an ugly black re-finish (only on the front - the back is the original sparkly gold color), and the original electronics were gutted and replaced with an improperly wired set of 1998 Danelectro electronics. It's all really quite ugly and was not done well, but I still love the guitar and would like to at least get the finish off.

It seems that the black finish paint can be chipped off in small pieces (and that there is also a red layer under the black). I'm not sure what type of paint it is, but I doubt it's anything fancy. Acrylic? Anyway, using a guitar pick, I was able to scrape it off from the edges. From doing this, I could see that much of the original gold finish is still present underneath. But as I move in towards the center of the guitar, it gets harder and harder to chip off the paint - probably because there is more of the gold paint there for it to cling to.

From reading on the forum, I can see that acetone and some citris based solvents can be used to remove a guitar's finish. But is there a way to remove these new top layers without affecting (too much) the bottom layer? For example, would brief applications of acetone perhaps help the top separate from the original layer? Or would it just cause it to melt together?

Another idea I had was to perhaps try short bursts from a heat gun - which I presume would loosen the cheap paint before affecting the original lacquer (which should be nitro).

Or perhaps I should just keep chipping away at it flake by flake (but this will take a long long time).

I would really appreciate some general pointers or advice before I try anything else. If anyone has any ideas, please let me know.

Here's a picture



Thanks - DT
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Lon



Joined: 30 Dec 2003
Posts: 6086
Location: Stephenville, TX

PostPosted: Sat Oct 28, 2017 7:34 pm    Post subject: Reply with quote

I have removed paint conditions like yours by dry sanding with 600 grit and block sanding until you start to break through the coloring. This is assuming there is a top coat layer over the base color. If the red is another layer over the base color, then you can be pretty aggressive with the black until gone, then repeat until red is gone.
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Sun Oct 29, 2017 12:48 pm    Post subject: Reply with quote

Hi Lon,

Thanks for your advice. Could you please clarify what I should do once I break through to the original finish? It seems to me that at that point, I would run a very high risk of also sanding off the original finish. How do I avoid that?

One thing that crossed my mind is that I could thin out the top coats with sanding, and then I could resume chipping off what's left with a nylon pick or scraper. Perhaps thinning it out would make it easier to chip off? And I already know that chipping, when possible, seems to allow for separation between the layers.

What do you think?

best,

DT
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Lon



Joined: 30 Dec 2003
Posts: 6086
Location: Stephenville, TX

PostPosted: Sun Oct 29, 2017 6:44 pm    Post subject: Reply with quote

When you break through a color layer, then use a finer grit like 1200 to complete the color removal. Remove the color and try not to break through the clear coat that may be present. You might have to test color removal process like under the pickguard or in the pickup cavity before going to the rest of the body

If you can chip it off, you might try compressed air to lift them. I stripped the clear coats off a MIJ pbass that had places that were delaminating using compressed air. That process didn't even touch the CAR color coat. Just a thought. Using any solvents may have a bad reaction
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Wed Nov 01, 2017 4:44 am    Post subject: Reply with quote

Hm... I think the paint on mine is too strongly attached for compressed air. What do you think about hitting it briefly with a heat gun and then chipping away at it? Would it be a good guess that the nitro layer less is susceptible to heat than the cheaper top layer paint?
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poolshark



Joined: 05 Jun 2014
Posts: 151
Location: Flahrida

PostPosted: Wed Nov 01, 2017 7:09 am    Post subject: Reply with quote

A heat gun is likely to do just as much damage as acetone would. Careful sanding is generally how this sort of thing is done, and it's a roll of the dice in even the most skilled hands. Besides, if I'm interpreting your picture correctly, it looks like the gold has been at least partially sanded off below the black and red layers. If you sand further, I doubt you're going to uncover anything worth writing home about. Unless you plan to refinish, just play the sumbitch.
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ladyfinisher



Joined: 21 Feb 2013
Posts: 401
Location: California

PostPosted: Sat Nov 04, 2017 1:22 pm    Post subject: Reply with quote

I have to agree. It looks like it was sanded before the black went on. There probably isn't anything there to salvage.

Ladyfinisher
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Sat Nov 04, 2017 1:52 pm    Post subject: Reply with quote

Hi. Thanks for your input. I realize it looks rough, but the back looks quite similar (with wear on the gold fading into the black underlayer etc.), and I'm fairly certain that it wasn't touched.

Regardless, I think my personal preference is to have an almost totally worn off gold than the black. My plan right now is to sand down to the red and then try to scrape off the red with a flat, rigid piece of nylon or plastic. Worst case scenario, I have to paint it all black again. I'll let you both know how it comes out.

Thanks - D!
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rickrob



Joined: 19 Oct 2011
Posts: 1083
Location: Massachusetts

PostPosted: Sat Nov 04, 2017 9:13 pm    Post subject: Reply with quote

The Groke wrote:
Worst case scenario, I have to paint it all black again.

Thanks - D!


If you like the gold and you end up with the worst case scenario-- why not try a refinish in gold?

Just my .02
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Sun Nov 05, 2017 1:59 am    Post subject: Reply with quote

hah... right, of course. I really meant "I just have to paint it again".

best - DT
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MapleOnMaple



Joined: 29 May 2007
Posts: 359
Location: Chi-Town, IL

PostPosted: Tue Nov 07, 2017 3:50 pm    Post subject: Reply with quote

Do not use a heat gun! You will not be able to regulate the heat enough for the paint to peel layer by layer.

Per everyone else's comment, I highly recommend wet sanding first with 600 grit. It is the safest way.

I have done this many, many times before and it will work on a flat surface. Never tried it in pickup cavities or routing but it is your best option. I would also recommend not trying to chip the finish as it will likely damage the underlying paint and wood.
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Wed Nov 08, 2017 2:38 am    Post subject: Reply with quote

Thanks for your input MapleOnMaple - I will take the (wet) sanding approach... and no heat. I'm still a bit uncertain as to what will happen when I actually get down to the gold. I expect that there is no way to avoid sanding off at least a tiny bit of that layer, right.

The scraping I did thus far was with a nylon pick - and the scratches you see where I did that were definitely not from the scraping I did - they were already there. But I'll refrain from doing this any more.

Thanks!

D
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MapleOnMaple



Joined: 29 May 2007
Posts: 359
Location: Chi-Town, IL

PostPosted: Thu Nov 09, 2017 9:07 am    Post subject: Reply with quote

Hey again,

Since the finish is very different, it may be easier to gauge how/when to stop. Your two finishes are also different colors, am I right?

When you sand with 600 and you see it open up a lil, switch to a less abrasive grade such as 800,1000 or 1500 depending on how much patience you have and your level of detail. You could do it all with 1000 grit, but you'll have to stay longer and sand the same spot til it wears through.

After you finish removing as much of overspray/other finish, you will want to step up to a higher grade sand paper and sand out all the scratches and buff with rubbing compound etc. It is very doable.

One last thing, when you see the finish open up in the center where you're sanding, move to the edges where the old finish is laying on top of the lower finish. You need to be aware of this to avoid sanding through the lower finish. Keep working the edges of the top finish outwards.
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Thu Nov 09, 2017 9:13 am    Post subject: Reply with quote

Hi MapleOnMaple,

Thanks for elaborating. It seems that there are two top coats over the original (black and red). I think I have the patience for it. Thanks for the support and encouragement. I live in Sweden, and we don't have many hardware stores - so I have to wait till I can get a ride out to one to purchase a proper sanding block. The stuff you can get in town is garbage. Will keep the list posted on the results. Perhaps I will discover something very ugly underneath - should be interesting.

best,

DT
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The Groke



Joined: 26 Oct 2017
Posts: 10

PostPosted: Fri Nov 10, 2017 2:33 pm    Post subject: Reply with quote

I just found this related link. Posting for the benefit of the next person who wants to try this:

http://www.tdpri.com/threads/i-need-to-strip-one-layer-but-save-the-one-below.318528/

I also just got some 600 and 1200 grit sandpaper. Will soak overnight for tomorrow.

Any opinions on using benzine instead of water to remove the overcoat? I'm a little worried about water run off warping the masonite (danelectro made guitars are made of 1/8 inch masonite sheets).

The guy in the link above used Naptha for part of the job. I can't get Naptha in Sweden... but I can get "chemical clean benzine," which is supposed to be similar. I used some once to clean tar off of a Harmony acoustic and it did not damage the nitro lacquer.

-DT
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