I have been varnishing sound boards for most of my career. It is my opinion that GOOD, high grade spar varnish, (Not these synthetic atrocities!), add something to the wood. (I know Del, don't start.) My method is to apply 1-2 coats of high grade, (and I identify it by smelling; from my years building/restoring boats), sanding with 150 grit between coats. Once I get the color and "fill" I want from the varnish, I put 2-3 coats of Varathane, (Professional Grade), sanding between coats with 180, then 220. After the final coat, I rub the well set final coat with 4/0 steel wool. After which, I apply 2 thin coats of Carnuba wax and buff. This whole process, is extremely time intensive, but it does what I want in color and sound. IMHO there is no easy way to accomplish this. The end results always please me. Regards, Joe Garrett, RPT, (Oregon)
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