Folding Utility Knife (print-in-place)

There are dozens of designs for utility knives using the standard trapezoidal blades, but I wanted a very compact one that could fit comfortably in a watch pocket. Most of the more compact designs use a sliding mechanism, which makes me a little queasy with the though of accidentally sliding it open as you shove your hand in your pocket. Most of the folding designs, however, are considerably bulkier. This compact print-in-place folding design snaps shut securely for pocket use and also clicks in the fully open position. 

Once printed, you'll see that it has a little blade retention latch shown in the second photo. You'll need to grab onto the thick part with some pliers and give it a little twist to break it free. 

To install a blade, close the knife and slide the blade in from the back as shown in the 3rd photo. When the blade is mostly in, open the knife and pull the blade the rest of the way forward until it clicks in place as shown in the last photo. To remove the blade, lift up on the latch as you push the blade back in towards the knife handle.

CAUTION: Use great care when inserting and removing the blade. And keep in mind this is a plastic knife handle not for heavy-duty use. If you really lean into it, it will break.

Design by LoboCNC on MakerWorld (license: BY-SA).