The varnish test rack is cocked to capture ûmaximum sun for a full half-day and a 24/7 ûdose of rain, snow, smog and dirt.

Paint and varnish shouldn't be too difficult to understand: They're coatings you apply with a brush, roller or pad to protect or beautify the surface to which, you hope, they stick like fury.

However, in clear coverings alone there are so many variations on the themes, between standard varnishes, oil-based treatments, urethanes, pigmented stains, two-part versus one-part treatments, and so forth, that we at Powerboat Reports sometimes get confused about the multiplicity of variations and capabilities we test. It is assumed, therefore, that it's confusing for readers, too. So as an introduction to this varnish exposure update, we thought we'd review the four basic types of coatings that we test.…