Abstract: A machine and method for semi-automatically attaching casing to a structural frame assembly is provided. The machine includes a support frame assembly, a fixed bank of stapling units supported by the support frame assembly, a movable bank of stapling units slidably supported by the support frame assembly and oriented substantially parallel to the fixed bank, and a head bank of stapling units located at one end of the fixed and movable banks and also supported by the support frame assembly. Each bank of stapling units includes a pivot bar, stapling units attached to the pivot bar for stapling the casing to the structural frame assembly, and clamping assemblies attached to the pivot bar for positioning and clamping the casing adjacent the structural frame assembly. The fixed and movable banks include jamb locators which are positioned to engage and retain the longitudinal edges of the structural frame assembly.