I am an amateur photographer. Several years ago I had the opportunity to purchase an entire darkroom setup.Now that I have a place to start it up I am lacking in one or two major components. Sinks.I know it is not boat building but I think i have decided on building the sinks instead of purchasing steel or fiberglass purpose built sinks.Cost is a factor .I will be using cabinet grade oak plywood .And I have a general idea on how the sink is going to look.My question is how would I go about waterproofing the plywood? It most likely won't be submerged in water or holding large quantities .But more or less to contain spills. I would like to retain the look of wood but if I have to paint it I am not opposed to the idea.