The 799-72008 is a Tamiya 4-Speed Worm Gearbox H.E.
The primary feature of this gearbox is a worm gear, which locks the output shaft when the motor is not turning. Its high gear ratios of 84:1, 216:1, 555.4:1, and 1428.2:1 make this gearbox appropriate for small walking robots, lifting mechanisms, and other applications where high torque is desired.
The Tamiya 72008 4-Speed Worm Gearbox kit includes one brushed DC motor and all the gears and parts to build any of the four possible gear ratio configurations: 84:1, 216:1, 555.4:1, 1428.2:1 . The four gear ratio options give you the flexibility to choose the best speed and torque for your project.
The kit includes step-by-step illustrated instructions in both Japanese and English. A scanned copy of the instructions is available on the Pictures tab. The kit can be built with just a screwdriver, but the instructions recommend having side cutters, pliers, and a modeling knife on hand.
This gearbox has a 4 mm diameter, round output shaft, which works with the wheels that are compatible with Tamiya 4 mm, round shafts and our 4 mm universal mounting hub. Our 3 mm universal mounting hub also fits on the smaller threaded end of the shaft, although it is not specifically intended to work with this type of shaft (the hub’s set screw could damage the thread on the shaft).
The low-voltage motor in this gearbox runs on 1.5-4.5 volts and draws up to a few amps when stalled, making it compatible with our DRV8833 motor driver carrier (2130-POLOLU) if appropriate precautions are taken to avoid stalling the motor.
The mounting holes on the gearbox are compatible with the Tamiya 70098 universal plate set and other Tamiya construction series products.
- One type 260 motor. For motor specs, see the Mabuchi motor RE-260 (#2295) data sheet (59k pdf).
- Four different gear ratios:
- Worm gear (locks the output shaft when the motor is not turning)
- 4 mm round output shaft (length: 100 mm) compatible with Tamiya wheels for 4 mm, round shafts and our 4 mm universal mounting hub.
- Assorted cranks
Note: The Tamiya 72008 4-Speed Worm Gearbox is a kit; assembly is required.
|Typical operating voltage:||3 V|
|Gear ratio options:||84.0, 216.0, 555.4, 1428.2 :1|
|Free-run motor shaft speed @ 3V:||9400 rpm1|
|Free-run current @ 3V:||150 mA2|
|Stall current @ 3V:||2700 mA|
|Motor shaft stall torque @ 3V:||0.97 oz·in3|
- 1- A theoretical speed of the gearbox output shaft can be computed by dividing this speed by the gear ratio.
- 2- This is the no-load current of the motor when disconnected from the gears in the gearbox; the no-load current of the entire gearbox with the motor connected will be slightly higher and will vary depending on the gear ratio.
- 3- A theoretical torque of the gearbox output shaft can be computed by multiplying this torque by the gear ratio.