I have a wooden sun with multiple wooden rays that has hung inside for several years. (Overall about 30" dia) We have decided that at this time it needs to go outdoors under the porch roof. It will not receive any direct sunlight. But it be exposed to temperature extremes and outdoor humidity swings. I examined the finish and tested it and determined it is solvent based lacquer. However the wood is only finished on one side. So I think I should put another coat of finish on everything to protect it as well as possible. Although there will be no sun exposure would spar varnish be better than regular varnish or poly? And must I do anything to the lacquer other than clean and sand to break the glaze to make varnish adhere well? Or would just another coat of gloss lacquer be sufficient front and back. My main question is what will stick well to the existing finish. Thanks