Tank Base for Lego rubber tracks

thingiverse

Inspired by the Tiny Trak concept, I designed a custom chassis for the TowerPro MG 946R servo motor - a standard size, 360-degree continuous rotating servo that's perfect for Lego rubber tracks with 34 teeth (680c01). I attached the servos to the chassis using M3x10 screws and gave the idler wheels an M3x30 axis. The round servo horn was glued securely into the drive wheel. Depending on your printer's tolerance, the idler wheels' bore may be snug - intentionally so. However, these wheels must spin freely on the M3 screws; you might need a 3mm drill to achieve this. To adjust the wheels' distance from the chassis, I used washers and a special M3 hex nut in my design. Once everything is in place, simply press the hubcaps into the wheels. Keep in mind that mine were printed hastily with significant stringing issues. The chassis features 5 holes (112 x 46mm and centered) to accommodate your own top deck design. Have fun building!