All begins with a 3D modeling.

2 sides, 2 axes, 2 washers and a T for water tubing, almost 20H later

NEVER TRUST descriptions of Asian products :)

The double shaft motor 5840-31zy 24v 470rpm is too weak for brushing tiles.

2.7kg.cm of torque was not enough.

Let's do a second version by improving motorization.