This is a hook knife that you print in two parts. I used ABS for testing and it holds itself together firmly with friction, for exchanging blades, though acetone could make a more permanent seal between sides. It's designed to be small enough to avoid cutting fingers. The finger hole is designed to fit 3 fingers with thin or no gloves and 2 fingers with winter gloves. I found it comfortable holding it a couple different way and the simplicity makes it easy in emergency situations. Simply place two DE razors on the 3 studs and press the two halves together. I am open to suggestions because I want to fulfill certain nitch needs. This design was inspired by Byron Leisek's paramotor crash. After a midair encounter with another pilot, he threw his reserve but his glider reflated and dove nose first pulling him faster towards the ground. He didn't have time to pull in his glider but had this hook knife been hanging from his carabiner, where his hands naturally were, he'd have had enough time to cut at least one riser's worth of lines. Coincidentally, he was also wearing bulky winter gloves when it happened. I want to apply my skills to these types niche issues that we run into while the sport is young, so that someday my children can experience safer flight. So if it's helpful to you, follow! Everything posted goes through real life testing. I will only post iterations of safe and working knives.
All testing is done as the stl is with no supports .2mm abs
with the exception of the attachments.
I suggest printing the hook knife in red and the case in the color of your choice.
with 30% infill it comes out at 2.48 ounces.
- 2 Standard DE razors
- Glue or ABS/Acetone (optional)
- 2mm thinner, making it easier to cut through fabric straps and seatbelts.
- reinforced thin area between blades, and moved it back making it easier to cut multiple lines at once (paragliding)
- adjusted angle of thumb
- added tether hole for attaching paracord.
- added 7th peg near bottom to further secure the two parts together
- removed fillet for strength and grip with thinner version
- The case is a yank away design with all attachments. A thumb lever makes it easy to load but in the event of an emergency, grab the handle and yank.
- v2 Case is designed to allow attachments that are friction pressed into place. Glue can be applied here for a more permanent fix.
- v2 Case velcro is just a flat back for glueing on velcro.
- there are two types of clips, the normal clip is meant to be removable for clipping to belt
- clipalt is an alternate design where once glued, it is not designed to clip easily off easily. It'd be difficult to clip on and off of belt but would be a more permanent mount to a strap style harness. (different sizes upon request)
- Squeezed just a bit more room out of the fingers hole.
- Added important notch that allows the hook knife to securely clip into case on both sides.
- Now hardware free! Everything is friction fit and removable!