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For my most recent builds, I've been using the Mohawk (formerly Behlen) Stringed Instrument Lacquer (M113-1406) with the recommended Mohawk Vinyl Sealer (M102-8000), both in aerosol put-ups. These were always in stock at my local Woodcraft Supply. From Mohawk's web site, you'd think that the use of the vinyl sealer was mandatory:

"Vinyl Sealer is also flexible by nature. Therefore, it is the only sealer that should be used under Stringed Instrument Lacquer. This combination yields great sound and empowers luthiers to finish their handiwork with confidence."

And the info on the lacquer rattle-can says the same thing.

The problem is that when I went to Woodcraft Supply to replenish my supply of the sealer, I was told that it was no longer able to be sold in California, and that they can't even order it for me. They recommended that I use shellac as a sealer (or a Zinsser "Bulls-Eye Sealcoat Universal Sanding Sealer" which seems to be basically the same thing). A call to the Woodcraft customer service center told me the same thing.

But when I called the Mohawk customer service department, I talked to a guy who said that it was perfectly fine to skip the sealer entirely. The only advantage of the sealer was that it speeded up the finishing process a little bit by making it easier to sand the instrument before the lacquer coat goes on. He told me that I could simply apply the lacquer coat, wait for it to fully cure, and then proceed with the subsequent coats.

So that's what I'm going to do. I'll report on the results. But I thought this information might be useful to others who use the aerosol version of the Mohawk Stringed Instrument Lacquer.*

*And now that I've finished writing this up, I can finally type the word "lacquer" without spell-check telling me that it's not "laquer.")

i no longer use any vinyl sealer and went back to shellac flakes . Vinyl sealer is softer than nitro and will let it dent easily. I also think there is less adhesion issues with shellac.

Interesting
I too have always used the vinyl sealer.
Doesn't shellac remain somewhat soft also especially in very warm climates?

no flake shellac is harder than vinyl I use ever clear for the solvent. You get better adhesion

When I talk about shellac we are talking about high end flakes not the crap in the can.
https://www.shellacfinishes.com/product ... ac-flakes/
I use super blond dewaxed and use a 1 lb cut for sealing. This is thinner than vinyl , harder and adheres a lot better, it sands easy and you get a thin coat. I use a rag and wipe it on.
Nitro stick a lot better to it. I had to thin the nitro hard to get it to adhere to vinyl

John,
If you use shellac after stain and after pore filling, do you sand the shellac after each application? Are there any adhesion issues with shellac and the water based pore fillers?
Thanks

It is sometimes difficult to pinpoint the culprit in a finish gone awry, but I no longer use vinyl sealer , especially over a porefilled surface. Like John, shellac is my go to seal coat. Shellac sticks to most everything and is harder than vinyl sealer. I used to wipe it on, but now I spray it, using a dedicated cheap spray gun from Amazon.

Bob Gleason wrote: ↑Tue Aug 22, 2023 7:03 pm
but now I spray it, using a dedicated cheap spray gun from Amazon.

How cheap? and is cleaning it a bitch?

Cheap as in $14.99 cheap. TOSUCS HVLP gravity feed on Amazon. Probably any cheap gun will work. Yes shellac is a little more difficult than lacquer to get out of the gun. I empty the finish out, put in a small amount of 180 proof and spray, empty out the alcohol and spray again until nothing comes out of the tip, refill and spray a second blast of 180 through it, empty the cup again and spray until nothing comes out of the tip. 2 rounds of straight alcohol works better for me than 1. As with any gravity feed HVLP, don't screw the lid on tight onto the empty gun reservoir. Even the slightest amount of finish on the threads can make the cap very difficult to get off. Since you are spraying alcohol, he process is not nearly as nasty as with lacquer thinner. Probably takes me 2 minutes to clean the gun.Gravity feed is a nuisance because you can't set the gun down without a holder for it, but not too hard to figure something out. Gravity feed works a lot better than suction IMO.

Well, this is a timely thread - I am just getting ready to spray vinyl sealer on four instruments. I have most recently been following John Hall's previous instructions faithfully, using Mohawk sanding sealer under the lacquer. JLT says you can just use lacquer. If so, how much should it be thinned for use as a sealer? And JLT says you have to "wait for it to fully cure". How long is that? Now it seems people feel it's better to use shellac. So I too would like to know if it works okay with water-based pore fillers like AquaCoat. And how much difference does it make to buy premixed super blonde dewaxed Zinsser shellac over mixing your own from flakes? (This may be faster for me at this point as I can get it from Home Depot locally; would have to order shellac flakes from Lee Valley or somewhere.) Bruce W.