Overview

These tiny, high-quality motors are intended for use at 6 V. 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. Lower voltages might not be practical, and higher voltages could start negatively affecting the life of the motor. All of the micro metal gearmotors have the same physical dimensions, but they come in a wide range of gear ratios—from 5:1 up to 298:1—and let you choose between two different motors: high-power (HP) and standard. This means you can choose the version that has the ideal blend of speed, torque, and current-draw for your particular application. Please see the table at the bottom of this page for detailed specifications, or look at micro metal gearmotor comparison table.

Gearmotor Dimensions

Micro metal gearmotor dimensions (units in mm).

This motor has a long (0.365" or 9.27 mm), 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).

Motor Accessories

• Wheels and Hubs: The micro metal gearmotor’s output shaft matches the Pololu wheel 32x7mm, Pololu wheel 42x19mm, and 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.

Pololu wheel 42x19mm with micro metal gearmotor.

A pair of Pololu universal aluminum mounting hubs for 3 mm shaft.

• Mounting Brackets: Our 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 42x19mm.

Black micro metal gearmotor mounting bracket pair with included screws and nuts.

White micro metal gearmotor mounting bracket pair with included screws and nuts.

Pololu micro metal gearmotor bracket extended with micro metal gearmotor.

• Quadrature Encoder: We offer a quadrature encoder for this motor that works with our extended bracket and 42x19mm wheel and provides feedback about wheel rotation (direction and speed). The encoder can be purchased as an individual unit or as part of an encoder set that includes two encoders, a pair of extended brackets, and a pair of 42x19mm wheels—just pick the particular micro metal gearmotor that best suits your application and you have a solution for closed-loop motor control.

Encoder for Pololu wheel 42x19mm with wheel, motor, and bracket.

Side view of the encoder for Pololu wheel 42x19mm, mounted to a bracket.

Oscilloscope capture of encoder outputs with the wheel spinning at 630 RPM.

• Motor Controllers: We have a number of motor controllers that make it easy to drive these micro metal gearmotors, including our qik 2s9v1 dual serial motor controller and our programmable Baby Orangutan and Orangutan SV-328 robot controllers. The inexpensive qik 2s9v1 allows variable speed and direction control of two small, brushed DC motors using a simple serial interface; the Orangutans combine a programmable Atmel AVR microcontroller and dual motor driver all in a single package and make interfacing with the motor drivers simple when you use our Pololu AVR library. All of the above controllers use the TB6612FNG dual motor driver, for which we also offer a simple carrier board.

Pololu qik 2s9v1 dual serial motor controller.

Baby Orangutan B-48/B-168/B-328.

TB6612FNG dual motor driver carrier.

Specs for the metal gearmotors running at 6 V

Pololu metal gearmotors arranged by size from left to right: micro, 100:1 and 24:1 mini, 35:1 mini, and 25:1 20Dx44L mm.

gearmotor	gear ratio	free-run RPM	free-run current	stall current	stall torque%22 (oz-in / kg-cm)	weight (oz / g)
5:1 Micro	5:1	2500	50 mA	360 mA	1 / 0.1	0.35 / 10
10:1 Micro	10:1	1300	40 mA	360 mA	2 / 0.2	0.35 / 10
30:1 Micro	30:1	440	40 mA	360 mA	4 / 0.3	0.35 / 10
50:1 Micro	50:1	250	40 mA	360 mA	6 / 0.4	0.35 / 10
100:1 Micro	100:1	120	40 mA	360 mA	10 / 0.7	0.35 / 10
150:1 Micro	150:1	85	40 mA	360 mA	15 / 1.1	0.35 / 10
210:1 Micro	210:1	60	40 mA	360 mA	19 / 1.3	0.35 / 10
250:1 Micro	250:1	50	30 mA	360 mA	22 / 1.6	0.35 / 10
298:1 Micro	298:1	45	30 mA	360 mA	25 / 1.8	0.35 / 10
5:1 Micro HP	5:1	6000	120 mA	1600 mA	2 / 0.1	0.35 / 10
10:1 Micro HP	10:1	3000	120 mA	1600 mA	4 / 0.3	0.35 / 10
30:1 Micro HP	30:1	1000	120 mA	1600 mA	8 / 0.6	0.35 / 10
50:1 Micro HP	50:1	625	100 mA	1600 mA	15 / 1.0	0.35 / 10
100:1 Micro HP	100:1	320	80 mA	1600 mA	25 / 1.8	0.35 / 10
150:1 Micro HP	150:1	200	70 mA	1600 mA	45 / 3.2	0.35 / 10
210:1 Micro HP	210:1	140	70 mA	1600 mA	65 / 4.7	0.35 / 10
250:1 Micro HP	250:1	120	70 mA	1600 mA	75 / 5.4	0.35 / 10
298:1 Micro HP	298:1	100	70 mA	1600 mA	90 / 6.5	0.35 / 10
24:1 Mini	24:1	410	70 mA	420 mA	4 / 0.3	0.80 / 27
100:1 Mini	100:1	140	90 mA	800 mA	15 / 1.0	0.80 / 27
35:1 Mini	35:1	350	70 mA	1500 mA	35 / 2.5	0.80 / 27
25:1 20Dx42L mm LP	25:1	470	60 mA	580 mA	7 / 0.5	1.70 / 48
25:1 20Dx44L mm	25:1	500	250 mA	3300 mA	40 / 2.9	1.70 / 48
67:1 20Dx45L mm	67:1	210	250 mA	3300 mA	57 / 4.1	1.80 / 51
154:1 20Dx47L mm	154:1	90	250 mA	3300 mA	122 / 8.8	1.85 / 52
19:1 37Dx52L mm	19:1	256	250 mA	2500 mA	40 / 2.9	6.40 / 180
29:1 37Dx52L mm	29:1	175	250 mA	2500 mA	55 / 4	6.40 / 180
50:1 37Dx54L mm	50:1	101	250 mA	2500 mA	85 / 6	6.60 / 187
67:1 37Dx54L mm	67:1	75	250 mA	2500 mA	100 / 7	6.60 / 187
100:1 37Dx57L mm	100:1	50	250 mA	2500 mA	110 / 8	6.80 / 193
122:1 37Dx57L mm	122:1	41	250 mA	2500 mA	125 / 9	6.80 / 193

%22 The stall torque should only be considered a rough estimate.

People often buy this product together with:

Pololu Micro Metal Gearmotor Bracket Extended Pair

TB6612FNG Dual Motor Driver Carrier

30:1 Micro Metal Gearmotor HP