iRobot Roomba 5xx 6xx 7xx Red CHM mod

Roomba Red CHM mod
How did I modify 5xx CHM with bearings

DISCLAIMER - Important!
- Phillips head screwdriver
- Old toothbrush or some other small cleaning brush
- Lithium grease
- Vacuum cleaner (to be use it in each step where you find dust and hair buildup. Be careful not to vacuum small parts as well.)
- Electric screwdriver or drill (This will be used as a kind of lathe that holds the gear wheel in order to contract its diameter.)
- Set of files, straight and round.
- Screw and nuts 4-40 or M3 to retain the small gear wheel to the drill.
- Step drill bits or any other tool that can help expand the housing holes diameter such as grinding stone, awl or a file.
- Swivel burrs removal tool. (This is a great tool to help in expanding housing holes.)
- Vise grips or a bit handle (This is to hold the drill bit etc. It is advised to expand the holes by hand and not with an electric drill to gain precise and more controlled process.)
- 3 sealed ball bearings with the following dimensions: (in x out x thick, Metric system) – 6x10x3 mm (for motor gear) – 10x15x4 mm (for small beater brush gear) – 15x21x4 mm (for large bristle brush gear)



- Motor wheel cylinder size fits bearing inner diameter of 6.0mm. Stop modifying at 6.3mm
- Beater wheel cylinder size fits bearing inner diameter of 10.0mm. Stop modifying at 10.3mm
- Bristle wheel cylinder size fits bearing inner diameter of 15.0mm. Stop modifying at 15.3mm

- Hole size for motor wheel fits bearing outer diameter of 10.0mm. Stop modifying at 9.7mm
- Hole size for beater wheel fits bearing outer diameter of 15.0mm. Stop modifying at 14.7mm
- Hole size for bristle wheel fits bearing outer diameter of 21.0mm. Stop modifying at 20.7mm
D. Voila – you now have a working iRobot Roomba with modded Red CHM gearbox.
Have fun and enjoy your Roomba, Avi
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iRobot Roomba DIY Guides by Avi
9-beep fix | power-supply conversion | speaker fix
5xx-7xx CHM cleaning | 8xx-9xx CHM cleaning
Red CHM mod | Gray CHM mod | battery rebuild
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Nice work! Seems like a wonderful improvement. Sadly, I just purchased (i.e., invested in) a fresh set of plastic gears already. Perhaps after these wear down I will revisit the situation.
Thanks for your comments. This mod deals with the wear of the gearbox holes. You better check this often before it is damaged. Bearings will prevent this from happening.