Lashed-lug boat

Lashed-lug boats are ancient boat-building techniques of the Austronesian peoples. It is characterized by the use of sewn holes and later dowels ("treenails") to stitch planks edge-to-edge onto a dugout keel and solid carved wood pieces that form the caps for the prow and stern. The planks are further lashed together and to ribs with fiber ropes wrapped around protruding carved lugs on the inside surfaces. Unlike carvel construction, the shell of the boat is created first, prior to being fastened to the ribs. The seams between planks are also sealed with absorbent tapa bark and fiber that expands when wet or caulked with resin-based preparations. Lashed-lug construction techniques are found in all the traditional boats of Maritime Southeast Asia, Melanesia, Madagascar, Micronesia, and Polynesia, and was one of the early maritime boat-building techniques that allowed the rapid expansion of the Austronesian peoples throughout the islands of the Indo-Pacific starting at 3000 to 1500 BCE. The lashed-lug technique of Island South-east Asia is considered to be very similar to that found in archaeological remains of some Scandinavian boats. This is considered to be a case of independent invention of one of a limited number of solutions to the same boat-building problem. The lashed-lug technique remains remarkably homogeneous throughout the entirety of the Austronesian range. The keel and the base of the hull is a simple dugout canoe. Planks are then added gradually to the keel, either by sewing fiber ropes through drilled holes or through the use of internal dowels ("treenails") on the plank edges. The most distinctive aspect of lashed-lug boats are the lugs (also called "cleats" by some authors). These are a series of carved protrusions with holes bored into them on the inside surfaces of the planks which are then lashed tightly together with the lugs on the adjacent planks and to ribs using plaited fiber (usually rattan, coir, and other palm fibers).