Could thermite sink a steel boat?

Lon Pennington: I also have access to simple chemistry equipment.

Joie Libutti: If you are thinking of "burning a hole in the hull, maybe not. The water on the outside may carry away the heat generated in the thermite reaction before melting a hole. Reaction of an acid would work, HClO4, if ir t was contained in a small area. An oxyacetylene torch would work if you are willing to go down with the ship.

Clement Viscarro: If you "had access to a boat"....... why on earth would you want to sink it? Insurance fraud?