As a knife lover, I have been looking for the perfect knife model ever since I got into 3D printing. Unfortunately, there was no model that met my standards, and eventually I started studying Fusion 360…

Introducing my simple, safe, and useful Utility knife!

✅ Features:

• 2-step length adjustment for various tasks
• Easy assembly without tools
• Safe and simple sliding button locking system

✴ Required:

• Utility blade
• Spring diameter 6mm, length 10~15mm
  • or Spring from an unused ballpoint pen (I used 4x24mm springs)
• (Optional) M2 12mm bolt and nut

⚠ The utility blade is very sharp, so always be careful!

Also, Do not use for work requiring strong force. I am not an expert and strength may vary depending on material and environment.

It is recommended to assemble it first before installing the blade to make sure all the parts work smoothly!

▶ Assembly:

• 1. Print all the parts, remove the supports, and trim them.

• 2. Place the blade on the holder and carefully slide the cap from the bottom up to assemble it.

• 3. Place the blade part on the handle, insert the spring, and then place the button.
      ( If you use 4x24mm ballpoint pen spring, cut the spring in half before use. )

• 4. Align the button with the top of the case, press lightly, and slide it up carefully.

• It is highly recommended to secure it with the M2 x 12mm bolt and nut in the hole at the bottom.
   
• Enjoy!

‼ Notes and Tips:

• Use a layer height of 0.15~0.1mm. The tolerance is set very delicately, so precise printing is required.
• Add support to the button and handle. (I used the supporter of the slicer because I don't have the skill to make the support myself yet :( )
• Uncheck the ‘’External perimeters first'' option to prevent overhang
• If you print the blade parts by flipping them left and right, it becomes left-handed friendly.
• Using a 15mm long spring will give you a more solid button feel.

Please give me feedback. I would like to improve this design as much as possible. 
and As some of you may have noticed, I'm not an English speaker, so I used translation. 
If there's anything you don't understand, please let me know in the comments.

I hope you all have a happy 3D life!
Also, if you like my design, you can buy me some beer.…

[https://buymeacoffee.com/tarinai_yonn](https://buymeacoffee.com/tarinai_yonn)