EDC Utility Knife – Swappable Shells

Overview

I wanted to make a printable utility knife… but also give it some personality.

The core design is simple, clean, and functional — it fits a standard utility blade, feels good in the hand, and goes together with just one M3 bolt and nut. But the themed liners really bring it together. I’ve made four inspired by versions: a Rebel pilot, an Imperial agent, a classic pink doughnut, and a NASA engineer.

It’s a practical tool with a bit of character — and way more fun to keep around on the bench or in your pocket.

Parts count: 7 + Hardware

Key Features

• Functional utility knife with stylish custom liners
• Accepts standard utility blades (Stanley-type)
• Ergonomic curved form factor for easy grip
• Four themed variants:
  • Rebel Pilot – Inspired by orange flight suits and resistance grit
  • Imperial Elite – Sleek black and grey with a cold edge
  • Doughnut Drip – Glossy pink with sprinkle-style detailing
  • NASA Engineer – Clean, high-vis white and grey with mission-ready lines
• Easy to assemble
• Blade held securely with a domed M3 bolt

Printing Details

Recommended filaments: PLA+, PETG, or ABS (for strength)

Hotend: 0.4mm Hardened Steel or brass nozzle

Print time: ~43 minutes

Filament usage: ~30g - 40g depending on shell design

Printing Tips:

• 0.2mm layer height recommended for detail
• 3–4 perimeters for strength
• No supports required
• Print shells in contrasting colors or use filament swaps for best effect

Assembly
Required hardware:

• (1x) 5mm domed M3 Allen bolt
• (1x) M3 nut
• (1x) Standard utility blade