Description: This gearmotor is a miniature (0.94" x 0.39" x 0.47"), high-power brushed DC motor with 250:1 metal gearbox, similar to Sanyo’s popular 12 mm gearmotors. These units have a 0.365"-long, 3 mm-diameter D-shaped output shaft.

These tiny brushed DC gearmotors are intended for use at 6 V, though in general, these kinds of motors can run at voltages above and below this nominal voltage, so they should comfortably operate in the 3 – 9 V range (rotation can start at voltages as low as 0.5 V). Lower voltages might not be practical, and higher voltages could start negatively affecting the life of the motor.

The micro metal gearmotors are available in a wide range of gear ratios—from 5:1 up to 1000:1—and offer a choice between two different motors: high-power (HP) and standard. With the exception of the 1000:1 gear ratio versions, all of the micro metal gearmotors have the same physical dimensions, so one version can be easily swapped for another if your design requirements change.

The gearbox has a long (0.365" or 9.27 mm), 3 mm-diameter D-shaped metal output shaft, and the brass faceplate has two mounting holes threaded for M1.6 screws (1.6 mm diameter, 0.35 mm thread pitch). It weighs approximately 0.35 oz (10 g).

Specifications:

• Gear ratio: 250:1
• Free-run speed @ 6V: 120 rpm
• Free-run current @ 6V: 70 mA
• Stall current @ 6V: 1600 mA
• Stall torque @ 6V: 4.3 kg-cm / 60 oz·in
• Size: 24 x 10 x 12 mm
• Weight: 0.34 oz
• Shaft diameter: 3 mm

Wheels and Hubs:
The micro metal gearmotor’s output shaft matches these Pololu wheels models: Wheel Pair, Wheel and Encoder Set and Wheel - White. These gearboxes also fit in other's Pololu wheels and the Solarbotics RW2 rubber wheel. You can also use the Pololu universal mounting hub to mount custom wheels and mechanism to the micro metal gearmotor’s output shaft.

Pololu wheel 32x7mm on a micro metal gearmotor.

Mounting Brackets:
These mounting bracket (also available in white) and extended mounting bracket are specifically designed to securely mount the gearmotor while enclosing the exposed gears. We recommend the extended mounting bracket for wheels with recessed hubs, such as the Pololu wheel 42×19mm.

Gearmotor with extended mounting brackets

Quadrature Encoder: We offer a Quadrature Encoder for this motor that works with our extended bracket and 42×19mm wheel and provides feedback about wheel rotation (direction and speed). Just pick the micro metal gearmotor that best suits your application and you have a solution for closed-loop motor control.

Gearmotor with extended mounting brackets

Motor Congrollers: You can use any L293 or other H-Bridge controllers with this gearboxes. It works well with the TB6612FNG Board, H-Bridge Motor Driver 1A or the L298N. These gearmotors are also compatible with the Arduino Motor Shield and the Ardumoto. Other motor controllers can be used as well, Pololu sells a series of motor controllers that can be used with these motors.