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When I remove the masking tape from the bridge area after spaying, there is a laquer ridge left there.
I have been very carefully scraping, attempting to feather the ridge off and still remain inside the footprint of the bridge.
This is very tedious and not very precise.
Can anyone offer up a better solution to removing the ridge?

Thank you for your time.

Carefully wet sand at high grit with a hard flat block. In the end, I've found it just as easy to scrape off the finish. Six of one, half dozen of the other...

I would be interested in an answer to this as well. I do the same feathering. What would really be interesting is a test where a piece of spruce is finished, then scraped for a bridge. Do the feathering, mount the bridge. Then after dry, do some cross cuts to see if there is an excessive glue line. Do the same test without feathering.

It might seem crazy, but what about using solvent in a pipette to "dampen" the wood at the ridge interface? Would that soften the finish enough to "sqeeze" the ridge down? Without creating any noticable finish artifact?

Mike

When I glue up a bridge I set the bridge on the top. I don't use masking tape anymore . Then I set masking tape and mark the bridge location . I keep about 1/16 inside the line and you rout a lip on the bridge so it sets in the "pocket"

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John Hall
blues creek guitars
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I like that Idea Route 1/16" Back on the bridge and , How deep into the bridge ? seems like it shouldnt be much ?

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I used to route a shallow rabbet on the bottom of the bridge, but getting the depth right, so it wouldn't show, is pretty tricky. These days, I have been removing the finish so the bridge fits "exactly" into the recess.
I think it was Pat Foster who posted a trick he uses & I was happy to steal his idea...
He uses a very sharp sewing needle set into a dowel handle to score the finish to the exact shape of the bridge. This is much easier to control than an Xacto knife & does less damage to the top because you can feel when the finish has been cut through.
Of course, the bridge must be securely pinned in the correct location & held down firmly as you work.
I angle the needle inward slightly & gently score right through the finish, then remove most of the finish with a sharp chisel, bevel up. Small scrapers & sanding blocks take care of the stubborn areas.
Small scraps of bone saddle material make great sanding blocks to finish up the rough bits. I cut some with a 45% (or so) angle on one end for getting into the corners.
I then use a scraper to make a very fine chamfer around the edges of the bridge. So far, this has worked very well for me.

to get that perfect fit I set the depth to the thickness of the lacquer. You can always sand the bottom of the bridge if you are a bit heavy. I use HHG or Fish glue for gluing them one.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
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Just what tool do you use to create the perfect rabbet around the base of the bridge?

Also, not sure what you meant by "I don't use making anymore ."

Mike

Doesn't using masking (tape) anymore...
That's why he routs...

Maybe a picture of the jig you use to rout the pocket in the finish would be helpful. Also a pic of the jig you use to hold the bridge while routing the tiny lip into it while you're at it.
Is the pocket in the finish cut flat on the bottom or curved to the top?

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I do the same as John .. I simply mask off the top area where the bridge will sit, and ten mark the bridge onto it with a pencil. Using an exacto knife, cut the tap using the bridge as a guide about 1/16 inside the pencil mark. Using the air die grinder router adn an/18 inch bit, set the bit depth so that you just route into the wood. I made a radiused mini router table out of plywood (sand the router table top in your bowl for a radius !!) and then set up a small round ended fence, and use another die grinder setup as the router mounted from underneath. Set the fence for about 1/16, and then route a couple scrap pieces to check the depth against the finish lip left on the guitars top. When that fits, route the bridge bottom for a lip. Then place and glue bridge !!!

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www.karol-guitars.com
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Ever since I started using paint stripper I have never gone back to all the other methods. I use nitro, finish the top and then hold the bridge in position and trace around it with a sharp exacto knife. Remove the bridge, mask off the top with some paper just in case I flick a speck of stripper. Take an artist paint brush and carefully paint the stripper right up to the knife tracing. Let it sit for 30 minutes, come back with a section of a single edge razor blade and lift the dried stripper up. Glue bridge. The first time I heard about this, I thought it was nuts (saw it on Charles Hoffmans website), but it really couldn't be any easier.

Glen, any particular brand of paint stripper?

Chuck

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Last time I did a bridge was to set the bridge with the pins,
make sure it's stable,
exacto around the bridge CAREFULLY!
then scrape with a sharp chisel and razor blade,
and a little sanding.
Worked well!

Last time I did a bridge was to set the bridge with the pins,
make sure it's stable,
exacto around the bridge CAREFULLY!
then scrape with a sharp chisel and razor blade,
and a little sanding.
Worked well!

Thanks guys, very much appreciated

Avoiding a ridge is easy if you mask with "frisket film" rather than masking tape. The film is available at art supply stores and commonly used by airbrush artists. It's clear and only 0.002" thick. Assuming you level in stages, you will end up with a perfectly level lacquer surface across the mask (note in the attached picture that the light reflection shows no sign of a ridge).

Personally, I prefer to have a perfectly prepared gluing surface on the top BEFORE I apply finish, so I prefer to mask. When the mask comes off (scoring around the outline and peeling), the top surface is uncontaminated and exactly the way I prepared it. Other than some possible cleanup around the outline, nothing else touches the top gluing surface.

I also rout a tiny rabbet around the edge of the bridge, so that the bridge overlaps 1 or 2 mm of lacquer, without interfering with contact at the glue line. The rabbet is created using a "micro-shaper" consisting of a laminate trimmer mounted upside down in a vice, and the base modified with an adjustable fence (made from a couple of stacked coins).

I made this based on stuff I saw on this forum 5 or 6 years ago. The StewMac Dremel base with a radiused table like Tony does. I also do test cuts on scrap to get the right clearance.
This is an old picture, now I usually only leave about a 32nd of finish in place so the ledge is smaller.

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I like the little jigs you guys use . I have something similar that sets on the inlay base. I set the depth to clear the lacquer , then rout , this will be a touch deeper ,and then I can sand the bottom for a perfect fit.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I don't like the idea of losing gluing surface just to get a (possibly) cleaner finish surface next to the bridge. My steel string guitar bridges are on the narrow side to begin with, only around 25 mm (1"). A 1/32" (.8mm) lip around the bridge, or 1.6 mm total loss of gluing surface fore and aft, is more than I like. Some leave a bit of finish under the bridge, without routing the ledge you guys are talking about. I've re-glued quite a few such bridges, so I like that practice even less.

I score lightly around the bridge after finishing, and scrape the finish away all the way to the line; no less, and hopefully no more! I suppose its possible to see that the finish has been cut, but if I've done a good of job, I don't mind the look. And at least you can see if the fit is good (or not).

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Chuck, I get mine from Walmart, I think it is called Kleanstrip. I use the semi-paste type and look for the one that contains methylene chloride (there is another one that contains friendlier chemicals, they may work fine, I've just never tried them).

This works, but I've never been successful in avoiding the wayward chisel ding. Last time I used my dremel, set to the depth of the finish (just a skosh, to use Robbie O'Brien's measurements). I used some Saran wrap on the top so that the dremel base didn't scratch the finish on hte top. Worked fine.

Tim - how do you accurately score around the frisket film? Are you able to see its edge clearly though the finish? Do you just "free hand" it or do you use some kind of guide for the blade? Thanks.

I score with an xacto knife, using a combination of free hand and straight or curved edges. Depending on the color of the wood top, you can usually distinguish the edge of the film quite easily, as the top underneath has not absorbed any lacquer. You can always highlight the edge (prior to finishing) with a sharp pencil that makes it even easier to see a line.

Makes sense. Thanks Tim!!