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SEALER QUESTION:
New Build
[*]Mohawk Stringed instrument lacquer.
[*]Spruce Top.
[*]Buff-through is over an area that was damaged from a fall and subsequently lacquered.
[*]bare wood, about the size of a half dollar.

My question is; what are your thoughts on hitting that bare wood with the vinyl sealer before lacquering the repair?
That would make the immediate area around the spot repair; WOOD-SEALER-LACQUER-SEALER-LACQUER.
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Posting the question here, I've just decided to go with lacquer over the small bare wood spot. I'm still interested in your thoughts though.

_________________
Measure Twice,

Karl Borum

Change up: Since I don't know any reason "not to", I applied the recommended sanding sealer to the local area of the bare wood. The posts that follow will be a repair log on any negative effects of doing it (applying Mohawk sanding sealer to a half-dollar sized spot of bare wood on an already lacquered and buffed lacquer finish). At least it will answer the question.

One wet coat of sanding sealer was applied to the spot, let dry for 45 minutes then lightly sanded with 320. Mohawk SIL lacquer will follow, probably 9 or 10 wet coats total, to the local area of repair. Three lacquer coats were applied today. It could take many, many months for any ill-effects to present.

While I've got the lacquer out:
I didn't know to sand a relief (radius) into the sharp edge of the binding. Last June this build fell to the concrete and required a top crack repair and relacquer and an eventual complete removal of the lacquer from the top. While performing this work, the sharp edge of the binding became a major issue for the re-lacquering. Today I realized that the sharp edge would also eventually become a major issue for the player's arm, if not corrected. So, I relieved the entire edge around the soundboard, to a pleasing radius, that will also require re-lacquering. I struggled with that decision for months and today closed the books on the decision. I trust it was a good one. I am feeling pretty ignorant and trying to fix that too.

_________________
Measure Twice,

Karl Borum

Bad dream of a repair.
Sealer over the bare spot- no problem.
Lacquer over the sealer- no problem.
Had some tiny pin holes that would not drop- fill with lacquer, many drops with 320 level sanding in between and pin holes would not accept lacquer (air pressure?). Made a decision to drop fill with CA (this turned out bad).

Scraping back the CA with taped razor blade (GLuBoost Pro REpair THin) the CA chipped off and removed lacquer.
Had to feather-sand the chips, then 9 additional spray coats over the repair. Final sand and buff were OK.

DONT KNOW WHY THE CA CHIPPED or WHY IT PULLED THE LACQUER OFF WITH IT.

_________________
Measure Twice,

Karl Borum

Sometimes the razor blade grabs the GluBoost and pulls out chips. I’ve had problems with this occasionally. You want to feel a smooth pull when you are scraping. Any catches will be chip outs so stop immediately. Sometimes laying the razor blade at a lower angle helps. Sometimes just take lighter passes. A razor blade with too large of a hook can also be an issue.