Ask the Staff
I would like to know if there is any product that can be applied to MDF to keep water from penetrating from a glass left overnight?
My topcoat will be enamel paint applied with a brush.
There is a reason varnish is used on the woodwork for a boat. Use a minimum of 5-8 coats. Cured varnish can withstand standing water. You just need to have enough film thickness built up so it is all finish that the water touches. The wood (or MDF), when completely encapsulated by the varnish, will not be impacted by the water, as long as the finish remains intact.
McCloskey Marine Spar Varnishes
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