Roomba S9 Side Brush Plastic Mount

The Roomba S9 vacuums have a small, green, injection-molded piece in the corner for the side brush.  This plastic piece had stripped out after several years of replacing the side brush.  Rather than replace the whole side brush assembly I removed the green piece and printed this replacement.

I recommend printing in PET or PCTG, solid walls with no infill. 0.2mm layer height.

To replace this piece:

1. Flip the Roomba over and remove the side brush (if not already removed).

2. Remove 4 screws around the main roller assembly.

3. Remove the roller assembly.

4. Remove the electrical plug to the side brush motor (you may need tweezers).

5. Remove 2 gold-colored screws holding the side brush assembly to the roller assembly.

6. Pull the side brush assembly through the main roller assembly.  This may be difficult if there is a lot of hair wrapped around the motor.  Push from the bottom and gently pull and rock the motor back and forth.  It will come free eventually.

7. Remove the green mount from the gearbox shaft.  It may be necessary to use side-cutting pliers or other tools to break it free, there are teeth on the drive shaft that keep it from sliding backwards.

8. Install the new 3D printed plastic mount. (printed orange in the image here)

9. Reinstall the side brush assembly through the hole in the main roller assembly.  It may be necessary to slightly sand the outside diameter of the plastic mount to fit through the hole depending on your printed part.

10. Reinstall all screws and pieces in the reverse order of steps 5 - 1.