About this 3D model
You'll need two bearings: inner diameter: 10 mm outer diameter: 30mm height: 10mm Mount them on the top and the bottom of the 'middle part' and put everything into the 'screw'.
You'll need two bearings: inner diameter: 10 mm outer diameter: 30mm height: 10mm Mount them on the top and the bottom of the 'middle part' and put everything into the 'screw'.