I really liked the design of the Inspire M3 Utility Knife, but wanted to add magnets for more positive closing and opening positions.   I also added a small tab to allow closing the knife with your thumb.

Both right and left handed versions included in the files.  

Tip: Print with 6 perimeters, no top or bottom layers, and 25% honeycomb infill for a cool effect.  (see photos)

Assemble with m3 screws and threaded inserts. The blade holder takes an M3 nut.  Add 4 8x2mm magnets to hold the handle open and closed.  Note: not intended for pocket carry. While the magnets provide a nice positive hold, it is NOT a safety lock. 

Hope you like it!