This 12mm brushed coreless motor ships factory-paired with a planetary gearbox in one compact assembly — the BLC1221 series, a brushed coreless gear motor for 3–12V systems. It's built for compact automation, medical device, and robotics drives that need a fast-responding, low-inertia rotor plus torque multiplication, without stacking a separately sourced gearbox onto a bare motor shaft.
A coreless rotor has no iron core wound with copper — it's a self-supporting copper coil spinning around a stationary magnet, so it accelerates and responds faster and more linearly than an iron-core brushed motor.
Several planet gears share the load around a central sun gear, so torque transfers through multiple tooth contacts at once, giving more torque per gearbox volume than a single spur reduction.
Building the two into one factory-matched unit means the gear mesh is sized to the motor's actual speed and torque curve from the start.
A factory-matched unit removes one coupling interface — and one potential source of misalignment — from your assembly; see Planetary vs Spur vs Worm Gearboxes Compared.
| Motor Model | Rated voltage | No-load speed | No-load current | Rated speed | Rated torque | Rated current | Stall torque |
| VDC | r/min | mA | r/min | g. cm | mA | g. cm | |
| BLC1221-01 | 12 | 2000 | 20 | 1280 | 3.7 | 120 | 80 |
| BLC1221-02 | 12 | 400 | 20 | 260 | 150 | 120 | 360 |
| BLC1221-03 | 12 | 80 | 20 | 52 | 700 | 120 | 1500 |
| BLC1221-04 | 12 | 16 | 20 | 10 | 3000 | 120 | 7500 |
For additional customization or reference configurations, please feel free to contact us.
Backlash, mechanical efficiency, and rated life all shift with the number of planetary stages inside the gearbox, since each added stage adds its own lost motion and friction.
Backlash, mechanical efficiency, and rated life all shift with the number of planetary stages, since each added stage introduces its own lost motion and friction.
BLC1221-01 targets speed-first jobs, BLC1221-02 sits in the middle, BLC1221-03 trades speed for torque, and BLC1221-04 is the low-speed, high-torque end of the range.
Speed-first jobs: 2,000 rpm no-load and 1,280 rpm at rated load, for small actuators or fan-like loads needing quick spin-up.
The middle tier steps down to 260 rpm and 150 g·cm rated torque for compact dosing drives.
Trades speed for torque: 700 g·cm rated torque at 52 rpm for small linear actuators.
The low-speed, high-torque end: 10 rpm rated speed, 3,000 g·cm rated torque, 7,500 g·cm stall, for mechanisms that hold or index a load.
Tell us your load and speed; the gear set can be adjusted from these four standard points.
For a smaller footprint with built-in position feedback, see the 10mm coreless motor with encoder, or for self-locking, right-angle output, the 12mm Coreless Motor with Worm Gearbox.
A load that just needs to spin, such as a small fan or a light rotary indexer with low friction, fits the speed-first profile of BLC1221-01.
A load that resists motion, such as a plunger, a small gear rack, or a friction-loaded hinge, needs the torque headroom of BLC1221-03 or -04, even though rated speed drops.
Check stall torque against your worst-case load, not just rated torque against typical running load, since stall torque is what the gearbox and windings see if the output jams.
If two adjacent ratios both look plausible, cycle time usually decides: pair the faster, lower-torque option with a mechanical advantage elsewhere.
All four BLC1221 variants share the same 12mm motor diameter, Φ12×L14.3 gearbox envelope, and mounting face, so a design built around one tier can swap to another without reworking the surrounding housing.
Output shaft end style (flatted, D-cut, threaded, or straight round) is confirmed against your coupler or driven part rather than fixed to one standard.
Lead wire length, exit direction, and connector style are adapted to your internal routing rather than left as a fixed pigtail length.
Same 12mm diameter, Φ12×L14.3 gearbox, and mounting face.
Flatted, D-cut, threaded, or straight round to match your coupler.
Lead length, exit direction, and connector style adapted to your routing.
PCB soldering and wire harness assembly added at build stage.
Dosing pumps and small diagnostic stages rely on a coreless rotor's smooth, cogging-free rotation at low current draw, which supports dosing accuracy and battery-powered instrument runtime.
A mid-ratio winding like BLC1221-02 is a common starting point for pump-drive torque bands in these embedded OEM builds.
Learn MoreCompact positioning stages and small actuator joints use the faster tiers, where repeatable, cogging-free motion at moderate speed matters more than raw torque.
The BLC1221-01 and -02 windings suit these drives, specified once and built across a production run.
Learn MoreGripper fingers and joint modules that hold position under load, rather than spin continuously, match the higher-ratio BLC1221-03 or -04 windings.
Stall torque headroom in those windings protects the mechanism if a finger or joint meets resistance.
Learn More
Each unit undergoes incoming inspection, in-process testing, and final verification to support consistent performance and dimensional accuracy from the first sample through bulk production.
Every unit passes incoming inspection to support consistent performance and dimensional accuracy from the first sample onward.
In-process testing supports consistent performance and dimensional accuracy through bulk production.
Final verification supports the batch-level consistency a design built hundreds or thousands of times over depends on.
SLW Motor's planetary gear motor design is covered by its own patent.
The company holds ISO 9001:2015 certification along with RoHS and Halogen-Free compliance reporting relevant to medical and consumer-facing equipment.
Each unit undergoes incoming inspection, in-process testing, and final verification for consistent performance and dimensional accuracy from sample through bulk production.
Matched to your available supply and target speed and torque point, beyond the standard 12V windings shown above.
Output shaft length, end style, and mounting interface adjusted to your coupler or driven part.
Brass, stainless steel, powder-metallurgy alloys, or engineering plastics, selected for load, wear, and environment.
Lead length, exit direction, and connector style matched to your internal routing.
Encoder feedback, PCB soldering, and wire harness assembly can be added at the build stage when the application needs closed-loop control, as shown by the 12mm N20 Micro Brushed Gear Motor with Encoder.
Buying a bare brushed coreless motor and a separate planetary gearbox from two vendors leaves the gear mesh, bearing preload, and output shaft alignment to whoever assembles them.
Factory-pairing removes that guesswork: the gearbox internals are matched to the coreless rotor's real torque and speed characteristics, and the coaxial output stays centered on the motor's own axis.
Planetary reduction isn't the only way to gear this brushed coreless motor family, and 12mm isn't the only size that fits every job.
For deeper theory, see DC brush motor vs the alternatives, planetary gear motor vs the alternatives, and the coreless DC motors range.
SLW Motor supports this platform through flexible sample customization and stable bulk delivery, working as an OEM/ODM supplier rather than a catalog-only reseller. Batch size and lead time for your specific ratio, voltage, and any added customization are confirmed against your actual order when you Get a Quote, and inquiries get a prompt reply with fast quotation feedback.
Share your target speed, torque, voltage, and mounting envelope and we'll confirm which standard configuration fits, or whether a custom winding, shaft, or housing material suits your build.
Batch size and lead time depend on your ratio, voltage, and customization, confirmed at quote.
Tell us your project or application requirements, and our team will get back to you with technical support, product recommendations, or a customized motor solution.
