Abstract: A unitary panel sorting and packing machine receives vinyl siding panels from an extruded production line. The machine includes a panel receiving section which includes lifting and flipper arms for selectively inverting panels for packing efficiency. From the panel receiving section, the panels are transferred to a panel accumulation section. The machine also includes a box folding section for folding corrugated paper box blanks along predetermined score lines. The box folding section is preferably parallel and adjacent to the panel receiving section and the panel accumulation section and includes retractable arms which selectively position the box in a ready position for packing panels therein. After the box is full, conveyor mechanisms carry the box from the box folding section through a box lid glue applying station and then into a box end folding and gluing station. This machine can substantially reduce repetitive stress caused injury to the operator.