Today I've seen an unusual boat: a pinnace's tender. They're usually made of steel and hang from a cat-head or crane over the steerage. This one's made of ply and the joints were filletted with black tar. The plywood panels looked a bit blackened by tar, too.
Worse, the rudder wasn't deeper than the keelson which was very deep indeed.
I wonder if that dinghy was purely decorative or could those matt ply panels stand sun exposure with no epoxy or varnish?
Fishing dinghies were painted but the chine joints were filled with tar. So were sewn boats.
Is that a waterproofing alternative ? Did one of you ever use it?