Excavator

thingiverse

Volvo EC210 model features a 1:20 scale, and its tracks hold sand-filled bucket from the kids' sandbox. The lower body part houses batteries with a modified design that accommodates a big Pb battery. Two servos in the arm offer 120 Ncm torque, while the main body servo boasts 260 Ncm. Cheap servos are used for track control and turning, costing around €2.5 each; these have been hacked to work continuously (search "pwm servo hack" online). The turn shaft's servo wires were combined to reduce connections from six to four. Tooth gears are bought from Conrad (DE) and can also be printed using Thingiverse's design #333018. The tracks are derived from Thingiverse model #36305, with thanks to LoialOtter for their contribution. The required parts list includes one set of each file except 3 washerSpacers, a bundle of trackTighteners (already containing 2 in the file), and 66 track elements; also needed are 2 trackGears/powerwheels, 2 powerWhlStabi, 4 counterWheels, 1 loeffel or printable loeffel, and 10 trackMiddleWheels.