12ga shotshell adjustable trimmer

Wanted a simple, adjustable trimmer that could accept a variety of blades to cut down 12ga hulls. This design will work with X-acto blades or even a section of break-away utility knife blades. Also, wanted a trimmer that uses very few non-3D printed components. So other than a blade, you only need one M6-1x25mm screw; that's it.

EDIT: After some thought, decided to make part 3 with a longer handle for better control.