To give the wheels more traction on different surfaces you can either attach the 8 tracks to each wheel, or attach 16 tracks to each side, in a caterpillar arrangement:

The tracks are attached to each other by using a piece of filament.

Troubleshooting

You may find that the tracks are a really tight fit when connecting up in the caterpillar track formation. There are a couple of solutions to this:

• print another track at 110% - 120% scaling on the Y Axis
• use TPU / flexible filament, as this can stretch
• use a pre-sized piece from Thingiverse