paul ,,air presure can be part of it, but the shellac on as sealer is not causing your trouble, and you can get glass with lacquer i have done it.. and i di rub it out with comet, actually it was the bar keepersfreind brand.. i had shellac as a base then 2 coasts of lac sealer then at least 7 or 8 coats of lacquer rubbed out.. lacquer goes on thin if your thinning it.. which i did at 25 to 30 % the spray system will make the job. and i have dry air paul, i run a water trap close to the compressor then another in the finish room and then another on the gun.
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