Apparatus for fabricating spacer frames from strip stock of different material including multiple work stations for treating the strip stock as the strip stock moves through the multiple work stations comprising: a) a corner forming station having a punch drive for moving first and second dies into contact with a flat surface of the strip stock at controlled corner locations along a length of said strip stock comprising: i) a first die assembly supporting a first die for deforming one side of the strip stock; ii) a second die assembly supporting a second die for deforming an opposite side of the strip stock; iii) a ram assembly including said punch drive and coupled to the first and second die assemblies for driving the first and second dies into engagement with the strip stock; and iv) a stop assembly for limiting movement of the ram assembly comprising first and second adjustable stops (410, 832, 834) on opposite sides of the strip stock path of travel which are contacted by the ram assembly to limit movement of the ram assembly to control deformation of the strip stock by the first and second die assemblies; b) a channel forming station for bending the strip stock into a channel having side walls; and c) a severing station for separating a lead spacer frame from subsequent spacer frames after the lead spacer frame has moved through the corner forming and channel forming stations; d) further wherein said first and second die assemblies punch material from respective strip stock edges to form corner notches and stamp the strip stock to define weakened zones in the strip stock for facilitating folding of the spacer frame at its corner locations. a) a corner forming station having a punch drive for moving first and second dies into contact with a flat surface of the strip stock at controlled corner locations along a length of said strip stock comprising: i) a first die assembly supporting a first die for deforming one side of the strip stock; ii) a second die assembly supporting a second die for deforming an opposite side of the strip stock; iii) a ram assembly including said punch drive and coupled to the first and second die assemblies for driving the first and second dies into engagement with the strip stock; and iv) a stop assembly for limiting movement of the ram assembly comprising first and second adjustable stops (410, 832, 834) on opposite sides of the strip stock path of travel which are contacted by the ram assembly to limit movement of the ram assembly to control deformation of the strip stock by the first and second die assemblies; i) a first die assembly supporting a first die for deforming one side of the strip stock; ii) a second die assembly supporting a second die for deforming an opposite side of the strip stock; iii) a ram assembly including said punch drive and coupled to the first and second die assemblies for driving the first and second dies into engagement with the strip stock; and iv) a stop assembly for limiting movement of the ram assembly comprising first and second adjustable stops (410, 832, 834) on opposite sides of the strip stock path of travel which are contacted by the ram assembly to limit movement of the ram assembly to control deformation of the strip stock by the first and second die assemblies; b) a channel forming station for bending the strip stock into a channel having side walls; and c) a severing station for separating a lead spacer frame from subsequent spacer frames after the lead spacer frame has moved through the corner forming and channel forming stations; d) further wherein said first and second die assemblies punch material from respective strip stock edges to form corner notches and stamp the strip stock to define weakened zones in the strip stock for facilitating folding of the spacer frame at its corner locations.