Gravity Utility Blade Knife – inspired by TIKTOK GRAVITY KNIFE FIDGET TOY

This is the best thing I've ever made! I have ~20 scattered around my house, stuck to things ready to cut things open.

It's a quick draw utility knife inspired by the TIKTOK GRAVITY KNIFE FIDGET TOY.

I'd strongly suggest printing out the TIKTOK GRAVITY KNIFE FIDGET TOY if you're prone to dropping things or cutting yourself, utility blades are sharp.

Required hardware (BOM):

• 1 x Utility blade with holes (I find these ones at the dollar store)
• 1 x M3 4mm Socket or Button Screw
• 1 x M3 4.2x3mm Threaded Insert
• 2 x 4x2mm magnets (optional)

Printing

Designed for printing with 0.4mm nozzle, 4 perimeters, >15% infill and in ABS.

Assembly:

1. Don't cut yourself
2. Slide in the blade
3. Insert the screw through the end hole in the blade and into the threaded insert
4. Slide the outer lock into place until it clicks
5. Insert magnets
6. Go grab a bandage and mop up any blood
7. Loosen things up. Tolerances are tight, you will likely need to slide the blade in and out many times using a hex key or similar. Eventually it will slide in and out freely and be able to be used like a gravity knife.

To use

To open

1. Flick up the lock (outer)
2. Hold at the back near the pivot
3. Let gravity slide blade out (always away from yourself and other people)
4. Close the lock
5. Use

To close

1. Flick up the lock (outer)
2. Hold at the front
3. Let gravity slide blade in
4. Close the lock