Abstract: A semi-automatic, hand-operated, pallet building machine is disclosed wherein a gantry assembly is movably mounted to a pallet bed assembly. The gantry assembly is provided with an operator handle, a pair of roller assemblies, and a hinged, spring-retracted nailer carriage which contains a plurality of impact dischargable nail guns. The bed assembly is provided with adjustable slots and jigs for receiving, supporting and aligning the stringer boards and deckboards of a pallet. In operation, pallet stringer boards and top side deckboards are placed and properly positioned on the pallet bed assembly utilizing the adjustable slots and jigs.