Replacement 3pi Ball Caster with 1/2″ Plastic Ball

Overview

This ball caster was originally released as a replacement part for the 3pi robot, but the 1/2″ ball can also be used a replacement part for the newer 3pi+ robot, which has the housing for the ball built directly into the chassis. This ball caster can also be used as a general-purpose ball caster: when mounted through a hole in a chassis that uses our micro metal gearmotors and our 32×7mm wheels, as on the 3pi, this ball caster is just the right height to keep the chassis level. The hole for this ball caster in the 3pi chassis has a diameter of 600 mils (0.6″) and has a side that is flattened by 30 mils (0.03″).

Replacing the 3pi Ball Caster

To replace the ball caster on your original 3pi, you will need to unscrew the rear battery holder (pull off the LCD and remove the batteries to access the screw) and gently bend the holder far enough out of the way to pull out the existing ball caster and slip in the new one. The battery holder is soldered to the 3pi PCB chassis on one side, so you will not be able to fully remove the battery holder. Take care not to lose the plastic spacer that is underneath the holder.

To replace the ball on your 3pi+ robot, simply pop the existing one out of the socket on the chassis and pop the ball included with this product in instead.

Note: This ball caster does not have mounting holes and includes no mounting hardware or spacers.

People often buy this product together with:

Pololu Ball Caster with 3/8″ Plastic Ball

QTR-8A Reflectance Sensor Array

Pololu Micro Metal Gearmotor Bracket Pair - Black