"Dragonfly" gravity knife, utility knife

This is a gravity knife with a unique mechanism inspired by AGA Campolin Dragonfly Gravity Knife

 

The knife holds standard utility blades, which are easily swapable. I have also included a version with a 3d printed blade.

 

 

*** Update 13.2.2026

Modified the blade holder slightly:

→ blade is now seated more securely

→ Open position of the knife is now sturdier

→ Allows slightly out of tolerance blades to fit the knife, without hitting the back pin

***

 

The assembly is really simple:

The mechanism might need a little breaking-in by wiggling back and forth.

I suggest adding a drop of lube to the inner side of the pins, but it will work without it: 

 

 

The correct blade dimensions (standard trapezoid blade):

 

 

Check out my other gravity knife model!

“Tri-Fold” gravity knife

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