63:1 Metal Gearmotor 20Dx43L mm 6V with Extended Motor Shaft

Overview

These cylindrical brushed DC gearmotors are available in a wide range of gear ratios, from 25:1 up to 488:1, and with three different motors: 6 V and 12 V motors with long-life carbon brushes (CB), and a 6 V motor with shorter-life precious metal brushes. All three motors offer similar performances at their respective nominal voltages, just with the 12 V motor drawing approximately half the current of the 6 V motor and with the carbon brush versions having longer lifetimes than the one with precious metal brushes.

The CB versions (shown on the right in the picture below), can be differentiated from versions with precious metal brushes (shown on the left) by their copper-colored terminals.

These gearmotors are optionally available with an additional 2 mm-diameter output shaft that protrudes 6 mm from the rear of the motor (see the middle picture below). This rear shaft rotates at the same speed as the input to the gearbox and offers a way to add an encoder, such as our magnetic encoder for 20D mm metal gearmotors as shown in the right picture below, to provide motor speed or position feedback.

20D mm metal gearmotor CB with long-life carbon brushes.

20D mm metal gearmotor CB with long-life carbon brushes and an extended motor shaft.

Magnetic Encoder Kit for 20D mm Metal Gearmotors assembled on a 20D mm metal gearmotor with extended motor shaft.

The gearmotors all have 20 mm diameter gearboxes and 4 mm diameter gearbox output shafts, so it is generally easy to swap one version for another if your design requirements change (though the length of the gearbox tends to increase with the gear ratio).

Please see the 20D metal gearmotor datasheet (1MB pdf) for more information, including detailed performance graphs for each 6V CB and 12V CB version. You can also use our dynamically sortable 20D metal gearmotor comparison table to search for the version that offers the best combination of speed, torque, and current draw for your particular application. A more basic comparison table is available below:

Note: Stalling or overloading gearmotors can greatly decrease their lifetimes and even result in immediate damage. In order to avoid damaging the gearbox, we recommend keeping continuously applied loads under 5 kg-cm (75 oz-in) for the versions with carbon brushes (12V CB and 6V CB) and under 3.5 kg-cm (50 oz-in) for the versions with precious metal brushes. Stalls can also result in rapid (potentially on the order of seconds) thermal damage to the motor windings and brushes, especially for motors like this that can deliver a lot of power for their size; a general recommendation for brushed DC motors is to limit continuous current to approximately 25% of the stall current.

In general, these kinds of motors can run at voltages above and below their nominal voltages; lower voltages might not be practical, and higher voltages could start negatively affecting the life of the motor.

Details for item #3464

Exact gear ratio: ``(28×28×25×25×25) / (14×14×10×10×10) = bb(62.5:1)``

Dimensions

The diagram below shows the dimensions of the 20D mm line of metal gearmotors (units are mm over [inches]). This diagram is also available as a downloadable PDF (99k pdf).

Dimensions of the Pololu 20D mm metal gearmotors. Units are mm over [inches]. This diagram only applies to the listed gear ratios.

Warning: Do not screw too far into the mounting holes as the screws can hit the gears. We recommend screwing no more than 3.5 mm (0.14″) into the M2.5 mounting holes.

Gearmotor accessories

• Mounting brackets: The gearmotor face plate has two mounting holes threaded for M2.5 screws, and you can use our custom-designed 20D mm metal gearmotor bracket (shown in the left picture below) to mount the gearmotor to your project via these mounting holes and the screws that come with the bracket.

Pololu 20D mm metal gearmotor bracket pair with included hardware.

20D mm metal gearmotor with a univeral aluminum mounting hub and mounted on a 20D mm metal gearmotor bracket.

• Wheels and hubs: The 4 mm diameter gearbox output shaft works with Pololu multi-hub wheels as shown in the left picture below. That shaft also works with the Pololu universal aluminum mounting hub for 4mm shafts, which can be used to mount our larger Pololu wheels (60mm-, 70mm-, 80mm-, and 90mm-diameter) or custom wheels and mechanisms to the gearmotor’s output shaft as shown in the right picture below.

80×10mm Pololu Multi-Hub Wheel installed on the 4mm D-shaft of a 20D mm metal gearmotor.

70×8mm Pololu wheel with 4mm hub adapter installed on a 20D mm metal gearmotor.

Alternatively, you could use our 4mm scooter wheel adapter to mount many common scooter, skateboard, and inline skate wheels to the gearmotor’s output shaft as shown in the left picture below. For a general-purpose hex adapter, consider our 12mm hex wheel adapter, which lets you use this motor with many common hobby RC wheels as shown in the right picture below.

A 20D mm gearmotor connected to a scooter wheel by the 4 mm scooter wheel adapter.

12mm Hex Wheel Adapter for 4mm Shaft on a 20D mm metal gearmotor.

• Encoders: You can use our magnetic encoder kit for 20D mm metal gearmotors to provide motor speed or position feedback. Please note that this kit only works on gearmotor versions that have an extended motor shaft.

Magnetic Encoder Kit for 20D mm Metal Gearmotors assembled on a 20D mm metal gearmotor with extended motor shaft.

Magnetic Encoder Kit for 20D mm Metal Gearmotors assembled on a 20D mm metal gearmotor with extended motor shaft.

• Motor controllers and drivers: We have a number of motor drivers and motor controllers that work with these 20D mm metal gearmotors. In particular, we recommend our TB9051FTG-based drivers, for which we have a basic single carrier and dual carriers in the form factors of a Raspberry Pi expansion board and an Arduino shield. Our VNH5019-based motor drivers (available as single and dual carriers) also work well with these motors, and because they can handle higher currents, they will run much cooler than the TB9051FTG carriers. The MP6550 motor driver is well suited for the 12V motors in applications with tight space constraints.

If you are looking for higher-level control interfaces, such as USB, RC, analog voltages, I²C, or TTL serial, consider our Motoron motor controllers, Jrk motor controllers, or RoboClaw motor controllers; these controllers are available in various power levels several of which can handle the 20D mm metal gearmotors (we generally recommend a motor controller that can handle continuous currents above the stall current of your motor).

• Current sensors: We have an assortment of Hall effect-based current sensors to choose from for those who need to monitor motor current:

ACS711EX current sensor carrier -15.5A to +15.5A.

ACS714 current sensor carrier -5A to +5A.

Selecting the Right Gearmotor

We offer a wide selection of metal gearmotors that offer different combinations of speed and torque. Our metal gearmotor comparison table can help you find the motor that best meets your project’s requirements.

People often buy this product together with:

Pololu Universal Aluminum Mounting Hub for 4mm Shaft, #4-40 Holes (2-Pack)

Pololu 20D mm Metal Gearmotor Bracket Pair

31:1 Metal Gearmotor 20Dx41L mm 6V with Extended Motor Shaft