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I recently put some blue painter's tape on a guitar top I had finished with brush-on varnish. I was masking off the bridge in order to add some finish to the bridge without screwing up the top. In pulling off the tape afterwards, I lifted an approx. 3/4" square chip of finish off the top at the treble end of the bridge. I'm planning to brush on a few layers of the same varnish to the spot and then sand and buff as usual. What I sorry about is what to do about the edges of the of the chipped area. There is an approximate 1/8" band all around the chipped area where the finish has lifted off the top but didn't pull off with the rest of the chip. Should I carefully sand away and feather-edge the lifted finish before refinishing the area, or...?

Needless the say I will be much more careful pulling off tape in the future. Any tips?

Thanks,
Max

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Max Bishop
Brighton, Michigan

Bump

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Max Bishop
Brighton, Michigan

I have had good luck with a bit of water thin CA for delam then med CA fill level and a french polish on top.

You need to have solid finish at the edge of the repair. Either cut back the finish with a knife util it is adhered properly or use CA as mentioned. Not sure what type of varnish you are using so witness lines at the repair edge may be inevitable but it will look better if you sand down the edges of the finish at the repair and feather the two together.

FWIW, this problem is likely an indicator of poor finish prep, coatings that have had a bit of dry time should not lift all the way to bare substate.

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Brian

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

https://www.howardguitarsdelaware.com/

Thanks, Brian and Fleck. FYI, the varnish is Petit Z Spar Captain's Varnish. It was recommended to me by Robert Ruck. I've used it on my last six guitars with good results.

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Max Bishop
Brighton, Michigan

I've heard that CA will discolor spruce. This guitar has an Englemann top with a shellac wash coat under the varnish. If I use thin CA for the delaminated varnish at the edges of the chipped area do I chance discoloring that area?

Max

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Max Bishop
Brighton, Michigan

Oil varnish is virtually always repaired with a Spirit varnish in the fiddle world. So any Shellac based varnish should work ok.

Anyone else on the discoloration issue with CA?

Thanks,
Max

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Max Bishop
Brighton, Michigan

Yes it can especially cedar. If your bridge is off you can check a small area. I read somewhere to seal the area with hide glue, I use shellac.

This is on an Englemann Spruce top with a wash coat of shellac under the varnish.

Max

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Max Bishop
Brighton, Michigan

If it is well sealed with shellac then I'd think it wouldn't discolor. I use CA for rosettes and have used it a couple of times for binding (I prefer titebond these days) and so long as things are well sealed with shellac there is no discoloration.

Thanks to all for your input.

Max

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Max Bishop
Brighton, Michigan