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Hello All,
Working at a turtle’s pace (a combination of being pulled away and being uber cautious - newbie jitters!), I am continuing my bridge replacement and belly bulge fix on the Giannini I have mentioned in previous posts. I have replaced the bridge. My intention was to use a ledge approach on the bottom of the bridge to avoid having any visible signs of the repair around the base of the bridge. Unfortunately, the damage to the top beneath the old bridge required some extensive levelling with a router and I could not get a solid contact between the bridge and the top using a ledge. I had to opt to tracing the outline of the bridge and drop the bridge in. Despite being as careful as possible, the end result left a very small but noticeable gap between the edge of the bridge and the top (see photo). I am pondering methods to fill the voids around the bridge to match the finish as best as possible. I currently do not have a spray booth so I am hoping there is a spot treatment I can use. My initial thoughts are to use a thick CA and carefully level and buff. Any suggestions for me?

Thanks in advance for your shared wisdom!

Cheers!
Rick

Trying to level and buff into an inside corner is darn near impossible. For the fill I would either use tinted lacquer or Glue-Boost CA. Try to keep the fill even so that leveling is not needed. I would look at this repair as more about disguising the white unfinished spruce instead of getting a truly level and filled surface.

Yeah that's gonna be a tough one. Shellac to match color and Gluboost to fill is probably what I would to do.

I would use Glu-Boost CA, work slowly and use my magnifiers.

Edit: went back and looked at the photo. I have to agree that a fine brush and shellac would be better for this one.

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Steve Smith
"Music is what feelings sound like"

I would not expend any effort on trying to hide this it is what it is. If you absolutely can't stand looking at it paint with an artist's brush some tinted shellac in there and call it a day.

CA is a bad idea because it makes any future repair more likely to damage the footprint outside of the footprint and it will show even worse. To remove the CA will take some of the remaining finish with it. And since this bridge has been off and you don't do this every day, the top was/is damaged, no insult intended it's likely it will lift again making keeping the repair "serviceable" an important goal.

John Hall has to replace bridges that Martin "pocketed" and we do too since we are Martin certified. He may have some advice for dealing with visible defects beyond the foot print. I would ask him too, PM perhaps?

We never use CA where it can result in gluing the bridge to the top because it's not reversible. I know CA is used for finish repairs but it's still glue and it still sticks stuff together.

But again Rick what you have now is a good, honest repair without anyone trying to cover anything up and that is appropriate for this instrument under the circumstances of how torn up the top was. If it were mine I would leave it as is and see how it does under string tension. If the bridge does not sling shot into the wall on the other side of the room this winter I might want to touch it up with some shellac.

Good going too on your repair efforts, nice to see and I'm sure you learned a lot too.

Thank you all, gentlemen, for your wise counsel.
I know the owner will not be overly concerned about the very minor gap. It is more a function of my near OCD tendencies and Virgo perfectionist curse that drive me crazy when I look at it. I will pull out my paint brush and try some colour matching magic and leave it at that. To your point, Hesh, I have learned a great deal taking this project on and so far, I am quite pleased with the overall results. My fingers are crossed that the sling shot scenario you painted does not come to fruition! :0)

Thanks again, folks!
Rick

FWIW those little white plastic toothpick type things with the feathery edge tips you can get at Stew Mac work really well for this type of fill.

https://www.stewmac.com/luthier-tools-a ... oothpicks/

I agree with Hesh on the no CA around the bridge. It would become another potential problem down the road. Also, from my experience, sometimes the fix is worse than the problem. Call it good, and drive on. You'll do better next time.

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"Act your age, not your shoe size" - Prince

Masking tape is your friend. And direct brush strokes into the repair and try to avoid pushing finish under the masking tape. Or mask everything off and lightly spray the medium into the repair. I've found spraying puts less medium onto the surface than brushing. Mask for an hour, spray for ten seconds.

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Peter Havriluk

If it’s nitro, don’t use blue tape!

Seconded we won't have any blue tape in our shop for this very reason.

I've never really had luck with any tape. I'd rather polish out some over fill then deal with tape edge build up. But that's just me. There are many way to skin a cat... Sorry poor kitty.