A maple sap line system and method for spin welding provides secure, unobstructed lines for collecting sap by creating a hermetically sealed connection between a lateral line and a mainline. A fitting connects the mainline to the lateral line. The fitting is spin welded to the mainline at a contact interface. The fitting comprises a protruding member that easily melts to create the frictional weld. The fitting has an elongated body comprising barbs that receive the lateral line. The fitting has a channel that enables fluid communication between the mainline and the lateral line. The flanges in the fitting register with a chuck to rotate the fitting against the main line at a high rpm. Molten debris formed in the channel is dislodged by drilling with a collared drill. The drilling provides fluid communication and creates a smooth inner surface in the mainline, and cuts off flanges from the fitting.