A method of manufacturing two or more composite parts, the method comprising: assembling the composite parts on a mandrel by laying a series of layers of bands of composite material onto the mandrel with a placement machine,—rotating the mandrel as the bands are laid onto the mandrel; attaching two or more debulk frames (10, 11) to the mandrel between opposed edges of the composite parts after the composite parts have been assembled; wrapping the mandrel, debulk frames (10, 11) and composite parts in a debulk bag; heating the composite parts,—forming a vacuum between the mandrel and the debulk bag so that the debulk bag is sucked into voids between the debulk frames and the heated composite parts and progressively presses against the heated composite parts whereby excess material is squeezed by the debulk bag towards their opposed edges; and removing the debulk bag and the composite parts from the mandrel.