I made a wooden kayak once. There was a lot of planing, sanding, steaming and bending, and took me a couple of months to get it right. It is way over what is needed for a Mordheim scale ship. The thing was a pain to maintain so I sold it to a buddy of mine.
All of the ships I made for my 28mm pirates I cut the basic shape out of insulation foam, sanded it down and add details like hatches, barrels, lanterns, blah blah, yada yada. They always turned out pretty good.