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Hello everyone. I recently did a neck reset on a friends guitar that I built him. I also cut out a sound port and shaved the braces. After resetting the neck, I had to reposition the bridge which I did and it plays just great now. After the process I had to refinish it. I used Behlen vinyl seale, then auquacoat filler, then de waxed shellac which was not sticking to some spots no matter what. I bailed on the shellac, applied more vinyl sealer and then Behlen stringed instrument lacquer from rattle cans. I leveled down the orange peel with no difficulty. But now some of the spots that weren’t taking the shellac are coming through Again and trying to level sand around the bridge made a real ugly mess. The top is the main problem. I’m thinking of stripping the top.
Would it be pushing my luck to remove the bridge and pick guard a second time so I can do a clean refinish. I’m afraid to Further thin out the wood in that area by scraping and sanding it again.
If I strip the top and get everything removed from around the bridge perhaps someone can give me tips on sanding/polishing around an installed bridge. I’m going to use a wipe on finish this time hoping this will reduce ugliness around the bridge. BTW it’s a sinker redwood top.
I tried to post pictures but I can’t seem to reduce the file size to 256kb that’s really small

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Alain
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Too many questions. Pictures would be helpful. You can use plain old MS Paint (the old version) to load your picture (right click, open with Paint), click resize, try a percentage (I find for my camera pictures to be used on this forum about 25 - 35% works), save (a new name is good). Right click the image and look at the properties, it will tell you the size.

Here are some pics. You can see the roughness around the bridge and a couple of shots where you can see the stuburn spots that nothing will stick too

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Alain
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I just reread my post. You’re right freeman too many questions. Sorry about that. What I really would like to know is if it’s wise to remove the bridge a second time and risk over thinning the top in that area by scraping and sanding there yet again.

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Alain
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I do not remove bridges on typical refinish work. You will need a chemical stripper to remove the mess you have on there. Sanding off finish to refinish acoustics is a bad idea in general and a really bad idea on soft spruce tops...

Not sure what the idea with the shellac was? Why a layer of shellac in a vinyl sandwich coat? The fact that it wasn't bonding should have been a big red flag and you should have stopped there and assessed the problem. My guess is silicone contamination as shellac generally seals down oils. Trying to simply "glue " it down with more sealer will not work, ever.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

I like your use of rope purfling on the sides - looks great.

Is a bridge relocation usually done on a neck reset??

Ed

Yup, I made a mess of it. This is number 7. I have yet to figure out a finishing process that works for me. So far wipe on finishes like Tung Oil have worked best for me and I think that’s what I’ll use once I strip this one.
Hi Ed. During the neck reset I over flossed it and then had to add little strips of wood as spacers to compensate thus causing the neck to shift position enough to have to move the bridge for better intonation. See pic below.
Hey Brian, how do you get a clean look around the bridge without removing it?

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Alain
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I guess my questions fall in two categories. First, how hard is it to remove the bridge (what glue) and is it necessary (is there any finish under the edge)? Is the geometry spot on after the reset? Along the same line, do you plan to remove the neck to finish around or under the f/b extension?

Second is your choice of finish and preparation. Do you plan to remove the finish to bare wood (chemical stripper?). Are their stains in the wood (maybe in a pore filler). Have foreign products (wax, silicon, fretboard oil) been applied that may give you adhesion problems? Are you comfortable with your products and schedule (I have used vinyl sealer and shellac under lacquer but have only used a oil finish twice and was not happy with it). What are you going to do at the edge where the new finish will interface with the old?

I've only finished one guitar with the bridge on, it was a classical and with care I was able to sand and polish up to the bridge. Bridges on classicals are usually finished - you could mask that off.

So I guess I don't have much of an answer, just a lot of questions. Its a lovely guitar, too bad this needs to be done. Let us know what you decide and how it comes out.

I’ve decided not to remove the bridge or the neck. I’ll strip the top with a chemical stripper then refinish it with a wipe on finish hoping I can wipe around the bridge cleanly without leaving any roughness to deal with. I’ll post my results. Thanks for the replies.

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Alain
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The easiest way is to finish over the bridge but most do not care for that. Other than that it's just careful hand sanding and polishing the last inch around the bridge.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Thanks Brian. As you can see from my bridge pics I have a hard time getting up close to the bridge sanding with the grain. I even made special little sanding blocks with pointy ends so I could get in there but it didn’t work. If I could sand parallel to the bridges edge against the grain I could make it clean but then the sanding marks show up big time. It’s seems to me that even if I don’t mask off the bridge I would still have that issue so I don’t get it and I’ve scoured the internet looking for solutions but the answer is always “ don’t install the bridge before finishing the top”. Perhaps it’s the extra orange peel that the rattle cans cause. I’ll try sanding parallel to the bridge before I strip it and then see if I can polish out the scratches. That’s why with my meager setup I’m thinking wipe on finish is the easiest solution. Tung Oil worked for me on other guitars. I Have also wiped on Behlen’s rock hard with success. Lacquer is just too toxic without a proper setup anyways.

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Alain
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From my extremely limited experience (3 acoustics, 1 electric, 1 Strat refinish) I find trying to spot repair in awkward places like this and / or refinishing with the bridge in situ (which I did twice due to a centre seam issue on #2, and once on #1 as I was not happy with the finish) is way more work than just removing the bridge, refinishing a flat surface, and re-attaching.

I decided to replace the bridge on #3 with a design that better straddled the X brace, and while I was at it, thin the lacquer on the top as I realised it was a bit thick when fitting the original bridge.

Because the bridge was off I was able to do 90% of the work with an orbital sander fitted with an interface pad, and machine polish it back up. This took a fraction of the time and the result is a mirror finish.

So my vote for a refinish if going that route would be to remove the bridge. Will those dull slots not polish out though?

Your guitar is stunning btw!! Out of interest, did you apply any finish to the top of the binding on the neck? Wondering what to do with the maple binding on another build.


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Hi Bosco. The problem with removing the bridge is that I have removed it and resanded the top once already and I don’t want to take a chance on sanding through the top by doing it a second time so I have to leave the bridge on.
Those dull spots will not shine up with anything I’ve tried including mcquires ultimate compound and renwax. Like Brian said it’s probably contaminated with something. It wouldn’t surprise me as I’m not very vigilant with the cross contamination thing. Something I will definitely work on in the future. One big thing that I realized is I would vacuum the sanding dust etc off the guitar with the same vacuum brush that I use for everything including the floor around my work area. Yes I was horrified when I realized I’ve been doing that for years. Stupid me, but I’ve learned a lesson and it will make me a better luthier. Ya that’s it.
Regarding the fretboard linings, I tape off the fretboard but leave a little bit of the top of the binding exposed and it will kind of blend in when I finish sand and polish

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Alain
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Totally understand your concern, but don’t you have to sand the finish off again anyway? Or were you planning on doing spot repairs to just those areas?

If you’re sanding back to wood I don’t see that the bridge being removed will make you any more likely to sand through. In fact I’d argue it would allow you to sand evenly with a foam block, this avoiding any thin spots.

Finally, my personal preference is to use compressed air rather than a vacuum. Far less likely to mark the guitar, especially when you’re as clumsy as I am!


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I’m using stripper to remove the finish. Actually I just finished stripping the top. It all came off right down to bare wood, even the crap in the corners near the bridge wiped away nice and clean. I wiped it all down with DNA and I’ll let it dry overnight. There is no finish under the bridge edges because I glued on the bridge before applying the finish.
Yes compressed air is a good idea after wiping the dust off with a micro fibre cloth.

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Alain
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So couldn’t you just remove the bridge for refinishing without having to sand more than if you didn’t remove it?


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If I did I would have to scrape or sand the glue residue from the top which is too risky since I have already done it once before. I used titebond.

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Alain
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Here’s a pic of the top after stripping it today. I didn’t have to sand at all.

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Alain
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Use a small scraper or a hooked razor blade to scrape away from the bridge and then sand into it with a small piece of sandpaper wrapped around a rubber eraser. Should leave it nice and clean. Once you get a film build you can sand across the grain no problem as long as you do not cut through to the wood.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

UPDATE

Ok, after stripping I applied 3 coats of extremely thinned out shellac wiped on. It went on very clean and thin. Then I used Hemp Oil. Wipe on and wipe off. Very easy and clean with no clean up required at all. Easiest thing I’ve ever done and it dried to a nice satin sheen. My new go to finish!!

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Alain
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