This gearbox is so strong/powerful and it can pulls a real car. All the plastics are 3d printed PLA. The gearbox uses 775 dc motor and the gear ratio of the gearbox is 98:1. The worm gear has 40 teeth. So the gear ratio in the worm gear mechanism is 40. Here there is a really high torque increase in one stage. I choose to go for helical gears on this one because they produce a lot less noice than regular spur gears and the forces on the teeth are transferred more gradually. Output shaft has a 20 mm diameter and I used 2x6004(ORS) roller bearing to support this output shaft.I was able to test the gearbox to a torque of about 43 kg*cm.During testing none of the gears broke, they were all printed in PLA.

Do not use this design in the professional field. Because you can't trust to plastic parts!

Below are all the parts I used in this project:
12V DC 775 Motor(100 Watt)
608zz bearing x3
6004 bearing x2
20 mm aluminium shaft
M8 threaded rod
Cotter pins
2x30—x4
3x50—x1

STL files for plastic parts: https://www.thingiverse.com/thing:479...
Editable source files: https://www.cgtrader.com/3d-print-mod...
More details: https://hackaday.io/project/178194-3d...

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Artist: Dan Henig | Track: Danger Snow
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