Spring-Axis Lock Folding Utility Knife II - F3DP

This is a fully 3D-printed folding utility knife featuring an axis lock mechanism. The locking spring is larger for improved durability. Additionally, the handle incorporates a scorpion-tail-like structure at the pommel that interacts with the locking mechanism—a uniquely engaging design!

This project is an upgraded version of a previous model. Beyond the new "scorpion tail," key improvements include:

1. 1.Optimized stress distribution: Internal snap-fit structures spread stress across the entire handle instead of concentrating it on single components.
2. 2.Thickened locking plunger: Enhanced rigidity, with pressure similarly dispersed to the handle.
3. 3.More secure blade fixation: Works entirely with 3D-printed parts or optionally uses M3-3mm/5mm/6mm screws and nuts for blade retention.
4. 4.Added pocket clip: For convenient carry.
5. 5.Significantly stronger without increasing print time or material usage—highly recommended over prior versions.

Downloadable Versions:

1. 1.All 3D-Printed Version (no hardware)
2. 2.Screw-Fixed Blade Version (requires M3 screws/nuts)
3. 3.Comb Version (blunt tool for toys/cosplay)

Blade Compatibility:

• •Designed for Stanley-style blades (62mm length).

• •Slightly shorter blades may cause wiggle; longer blades may not fit.

   

  

Printing:

• •Requires only one support and one brim.
• •Print time: ~1.5 hours.

Assembly:

• •Not difficult but requires careful reading of instructions.

• •Strongly recommend watching the assembly video .

Assembly Steps (Summary):

Show all components.

Snap the orange pocket clip into blue handle’s internal slots (firm force needed).

Engage spring and locking plunger via snap-fit.

Insert spring assembly into handle.

.Join orange and blue handle halves.

Mount blade holder to pivot; install orange "scorpion tail" at handle base.

Close the other orange handle half.

Snap the second spring into red locking plunger.

Close blue handle half: first secure the base, then use a tool to adjust spring interference if needed.

Fix all parts with two circlips.

Install blade using M3 3mm-6mm screws/nuts; optionally use white parts based on screw length.

The strength of 3D-printed knives cannot be guaranteed and they are suitable only for light-duty tasks, such as cutting paper or opening Amazon packages. Unless otherwise specified, all of my knife designs are intended for light-duty use only.

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