I always use a good exterior varnish or a marine varnish that can withstand UV rays. I am currently refinishing 8 boards for a 51 and so far have applied 3 coats underneath and three coats on top. I cover the grooves and sides/ends also. Between each coat I use 220 grit sandpaper and on the final coat (which will be #5) in lightly sand with extra fine steel wool to eliminate any roughness such as a tiny bubble, etc. Comes out looking like glass.

1954 Chevy 5-Window FINISHED
1951 Chevy 1/2-ton pickup [b]FINISHED[/b]

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