This is a customizable adapter to convert a round door knob into a door handle with a lever.

At the ideal size the nut and bolt sides will clamp together tightly right as it reaches the desired grip on the door knob. If you aren’t getting enough grip to your door knob, try adding a very thin strip of poster putty around the door knob before clamping the lever on.

This is designed to be held on with an M5x18 bolt and an M5 nut.

Fabrication and Assembly Instructions

Device instructions:

  1. Attach device on to existing round doorknob using provided nut and bolt
  2. Use the doorknob as though it was a door lever


  • FDM 3D printer
  • Material: PLA
  • Nozzle Size: .4mm
  • Layer Width: .2mm
  • Supports: Yes
  • Build Plate Adhesion: Skirt

Print this yourself!

Credit: rcolyer

Our devices are available to Illinois residents free of charge. However, we do accept donations to support program costs.

Suggested Donation