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So far all my archtops have been Behlens nitro over their vinyl sealer.
For my current build (European spruce/maple) I want to use garnet shellac for it's deep rich color. How best to apply it? nitro over shellac over vinyl sealer? nitro over vinyl sealer over shellac? or simply nitro over shellac?

Nitro over shellac. If you're going to the trouble of using shellac, then you won't find a better sealer.

How about tinted Nitro over nitro over vinyl sealer?
With nitro over shellac over vinyl sealer - by the time you build enough garnet shellac to impart much color you may cause adhesion problems with the nitro top coat.
With shellac over nitro over vinyl sealer - you will be putting a less wear and chemical resistant top coat with color in it over the nitro. You would do just as well or better to just use shellac over shellac over shellac. With that you could create a vignette effect on the top by coating the edges a little heavier.
With nitro over shellac - again, by the time you build much color you might have adhesion problems. Shellac in a thin coating makes a good barrier coat for many finishes, and will stick on top of many finishes, but if "built up" other finishes don't stick that well to it.
Nitrocellulose lacquer can be tinted with alcohol or solvent based dye stain, and again, by selective spraying you can shade the wood to place the color where you want it. You could spray your sealer coat, followed by a couple of coats of un-tinted nitro followed by tinted coats followed by a few more clear coats to level without cutting into the tinted coats.

Shellac first, give at least 24 hours curing time, then your vinyl sealer, then soon after your nitro topcoat. You’ll probably be happiest if you can achieve your desired depth of colour with the garnet shellac on bare wood. Do a trial.


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Burnish your shellac into the wood using a paper towel and circular motions. I've begun using this as a base coat on all my nitro finishes. It brings out the chatoyance of the wood wonderfully, and it virtually eliminates the fuzzy grain on bare spruce that sealer causes. Any, shellac sticks to anything and anything sticks to shellac.

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