We can understand how clear wood coatings exposed to the elements
can last for years by learning how and why such coatings fail. The “why” is three-fold: Water attacks the coating or the wood, ultraviolet light (which is an invisible part of both natural sunlight and interior fluorescent light) does the same, and the wood substrate moves .
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Above is from the article .. paint scientist said it ... not me . There it is in a nut shell .. Reading that it tells me UVL attacks the surface inside the house too . It says flouresent light , so I assume shop type flouresent lights .. not light bulbs ,, even though alot of the new energy saving lights are flouresent .. Jake/Fred .. I have the same problem .. read a bunch of times like your pounding it in a concrete block ..
