Ferrex Smart 800 - all terrain replacement wheel

After three years of daily use, the original wheels regularly began gunking up, slipping and made the robot stuck, waiting for help…

…I measured the original ones and made replacement ones: wider and with spikes! Idea is to reduce grass and mud sticking to it and improving grip. Spikes are designed with asymmetric angles in a way that support is not needed all around the model.  Internals of the wheel have been modified from easy injection moldable to easy printable; Added protection cap for central nut to avoid dirt ruining the thread instead of original big snap in protection cap for more easy printing.

Print needs support on for internal geometry transferring the torque. I printed in PETG with 4 perimeters, 25% infill and 0.24 layer hight. Since the wheel hit the size limit of my modified Ender 3, I split the model to 5 parts, the hub and four segments, bolted together with some M3 screws. 

Each wheel needs more than 30 hours printing time and takes about 300g of filament each.

Looks massive on the robot :-)