Robot Wheel spacer 4mm

This is a wheel spacer i have designed for one of my robotic projects as i found the axle length of these wheels to be too small to hold the wheel on while the motor is mounted into my custom chassis, this spacer is designed to have a tight and snug fit to grip the motor making the wheels far more secure. To install this roughen up both mating surfaces and then apply super glue to both surfaces and line them up perfectly hold for 30 seconds then allow to dry for a few hours, it is a good idea to