The exterior aluminum extrusion first passes through the knurling block. Two sets of steel blades cut serrated edges at 4 locations within the Insulbar cavity. The serrated edges or knurls create a mechanical lock between the aluminum cavity and the Insulbar profile. The two insulbar profiles are immediately inserted into the knurled aluminum cavity and the entire extrusion is mechanically moved to station 2. The interior aluminum extrusion is placed to ride over the top of the exposed Insulbar profiles. The extrusion is also knurled prior to mating with the Insulbar. The extrusion is mechanically moved to station 3. Sensors direct air plungers to square the completed window extrusion before the rolling process. The combined aluminum and composite section passes through the computer controlled rolling machine. This machine uses a series of steel discs, which the composite section passes through, pushing the aluminum into the Insulbar. This creates a mechanical lock that holds the composite section together.