For my strange brand of photography, I am required to cut 16awg copper sheet into rectangular chunks - 4x5" and 6.5x4.5". To do this I use a device called a Plate Shear (see picture).
(oops... imagine that the bottom blade is actually just a flat surface. The bottom blade ISN'T curved like that.
The problem with this arrangement is that as you pull the lever down to perform the cutting action (bringing the two curved blades toward each other), the workpiece has a tendency of pulling into the shear. The bottom line is that I can't ever seem to get a square cut with this thing.
Can any of you inventive souls come up with a jig that could help me out?