Fish eye. Caused by any of several types of contamination on the surface of
the wood that changes the surface tension of the finish over the area
causing the finish to flow away from the contamination. Silicon is a primary
candidate because once something is contaminated with it it's a bitch to
Commercial fish eye eliminator will correct the problem but you have to be
cautious with it since. It's usually a silicon and if you get it on anything
else, including tools or applicators, that will, in turn, become
contaminated and you enter a vicious circle.
Best bet is to seal it off from any subsequent layers is one or several thin
and lightly applied coats of finish. Dewaxed shellac will work also. Saw an
article on a couple of methods for doing so but can't pin it down right now.
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