Added opening to see pins moving

Clean and Prep

• Remove any supports from the printed parts.
• Sand the inside of the cylinder where the supports touched, so it’s smooth.
• Insert Key and Pins
  • Slide the key into the cylinder.
  • Place the larger pins (with rounded ends) into the cylinder so their rounded sides face the notches on the key.
• Align Cylinder and Core
  • Position the cylinder tip into the core, ensuring the slot for the locking clip aligns with both the cylinder and the outer core.
• Add Springs and Smaller Pins
  • Push the cylinder in until the first hole is visible.
  • Insert a spring into that hole.
  • Take one of the smaller pins (no rounded ends) and place it on top of the spring. Use the pin to compress the spring enough to slide the cylinder fully over it.
  • Repeat this process for all four springs and pins.
• Secure with Clip
  • Once the cylinder is fully seated, insert the locking clip. This prevents the cylinder from sliding back out.
• Final Touches
  • Test the mechanism.
  • If it sticks, sand any rough spots and consider adding silicone lubricant.
  • My recommended springs: Amazon link (4.5mm diameter, 18mm length). Pen springs can work, but assembly may be trickier.