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So, I got overenthusiastic yesterday and put the first coat of Zinsser's French Polish on my guitar top. Unfortunately, I forgot to mask off the bridge area before applying finish.

My plan is to mark my bridge outline on a piece of posterboard and cut it out. I'll wipe alcohol in that general area to cut down the finish, then lightly sand in the cutout area to make sure I get down to bare wood. Then use light masking tape (the blue stuff?) and reapply finish to the top.

Any better suggestions?

I would finish complete, scribe with razor knife and scrape with cabinet scraper and burnished razor blade. this is the proceedure I always use. It is difacult to sand in that small of an area with out getting un-level

Finishe the guitar, buff it out then mask off a large area and locate the bridge. Draw an outline aorund the bridge with a sharp pencil. Take a razor blade and cut the tape about 1/16" inside the line that you drew and remove the inner portion of tape. Now set your laminant trimmer to cut just through the finish, remove the tape and glue the bridge down and your done.

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tim...
http://www.mcknightguitars.com

Yeah, I was hoping to be smart on the front end by masking the area first, so I could avoid scraping (no laminate trimmer).

I will follow your advice - it seems like it would be better to do the traditional method, rather than trying to change in the middle of the process.

I always finish the whole top and buff it out to begin with. Then I will lightly scribe around the bridge with a needle. After which I do like Tim and cut about 1/16 inside with a razor blade. Clean the finish out with your weapon of choice. Mine is usually a sharp chisel. Never thought of using my laminant trimmer. Sounds scary , but it would probably do a great job and would be a lot faster.


Josh

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Josh House

Canadian Luthier Supply
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House Guitars - Custom Built Acoustic Instruments.
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I have tried to pre-mask but found that the finish would seep just a little and when the tape was removed It would often chip the finish.

The one thing I did have a bit of success with was gluing the bridge in place carefully coating (only) the bridge with art mask. Being very careful to get the bridge completely covered without leaving any on the top by trimming the mask back to the seam with a razor. (very tedious) Then I sprayed the finish. After the finish cured I removed the art mask then buffed. But I have to tell you that I spent four hours getting the art mask on just right. Also you have to score the exact seam of the bridge and top with a razor before removing the art mask. This worked very well for me but ended up taking more time than the traditional method and made buffing a bit harder.

For those that don’t know art mask is a paint on gum with a very low adhesive property. I can be rubbed off very easy with no residue left behind. You can get it at any art supply store.

I found a pretty good trick in the Stew-Mac video --- just finish everything without the bridge in place, and when you are done polishing, set the bridge in place with double-stick tape and scribe around it with an exacto. Then take a cheap little paint brush and applhy finish remover within the area of your exacto-scribe. Wait a few minutes, then scrape the laquer/remover goo away carefully with a chisel. I was surprised how well this worked.

Charles Fox showed me a router base, can't remember if it was a Stew Mac dremel base or PC 7310 base, that he had modified for cutting out the lacquer for the bridge.

It was simply a standard base with a piece of thin felt material glued to the bottom. He said he set the bit basically flush, then when he held it down the felt had just enough give to cut away the thickness of the lacquer.

Haven't tried it yet, but I have 2 hanging up now and should be trying it on them soon ( after a little practice on scrap first).

Still have to trace around the bridge with a knife to get the outline.

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Dave Rector
Rector Guitars

I found that in masking the bridge I had trouble when polishing. Because I wet sand it would cause the area under and around the bridge to swell and just made too much mess. I now finish the whole top, do all my sanding and buffing then put down a layer of wide masking tape, locate the bridge and pin it. Then I scribe around it and remove the tape from inside the footprint and using my dremmel with the stewmac base set the bit very carefully, lowering just a bit at each adjustment till I'm just taking off the finish. You can rout very carefully right up to the tape and then use a small chisel to clean up anything that is left. I usually tape the bottom of the dremmel base with tape also just to avoid any scratches. This has given me the best results and it is much faster and cleaner than trying to chemicaly remove or scrap the finish.

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Tickle your guitar daily, and it'll tickle you back.

John you are correc and I am amiss for not having mentioned so in my post that sanding up to the bridge is very hard to get level and clean. This is another reason I abandoned this method after the fist try. Things are much easer if ther is nothing to get in the way while spraying, French polishing (if this is you method of finishing), level sanding and buffing.

I always rout the finish away after buffing the guitar. But MichaelP, that art gum sounds like just the thing to keep all that glue squeezeout off the bridge when cleaning up. I just hate it that I polish the bridge, glue it down and then have to repolish because it has water/glue staining.

John, I am not going to talk about the bridge that I glued on before French polishing. Talk about disaster...But I am not going there

Well, Michael, I'm glad I didn't go with my smart idea #1, then (gluing the bridge first).

A different John

Way more problems than you want to deal with.