Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
When a stripped or undersized gear stalls your RC car, robotics project, or miniature actuator build, finding a dimensionally accurate replacement with reliable bore fit is the real challenge. This 0.5 module 24-tooth brass pinion spur gear is engineered for makers, hobbyists, and small-scale mechanical engineers who need repeatable, tight-tolerance power transmission in confined spaces.
Each gear is machined from solid brass, offering a balance of machinability, moderate corrosion resistance, and low-friction meshing. The module (Mod) is 0.5, with 24 teeth and a pitch diameter of approximately 12 mm (0.47 in). Bore options span 4 mm, 5 mm, 6 mm, 6.35 mm (1/4 in), and 7 mm to accommodate a wide range of motor and shaft diameters. Face width is typically 5–8 mm (0.20–0.31 in) depending on variant.
Typical use cases include: replacing worn pinion gears in 1/18–1/24 scale RC vehicles, driving encoder shafts in desktop CNC and 3D printer extruder assemblies, and building compact gear reduction stages in educational robotics kits and servo-driven mechanisms.
Machined from brass for reliable dimensional stability, smooth meshing, and resistance to galling under moderate loads — a dependable choice for low-to-medium torque drive trains.
Standard Mod 0.5 tooth profile ensures direct interchangeability with any compliant 0.5 module mating gear or rack. Pitch diameter ≈ 12 mm (0.47 in) for compact gear stage design.
Choose from 4 mm, 5 mm, 6 mm, 6.35 mm (1/4 in imperial), or 7 mm bore to match your motor shaft directly — no bushing or adapter required in most applications.
Available in 1, 2, 5, or 10-piece packs. Stock up for prototyping runs, spare-parts inventory, or multi-axis builds without overpaying for single-unit pricing.
Brass-on-brass or brass-on-steel gear pairs run quietly with minimal lubrication, making these gears well-suited for noise-sensitive or lightly lubricated environments.
Brass is readily drilled, reamed, or tapped for set-screw retention, allowing custom shaft-fit modifications without specialized tooling.
| Module (Mod) | 0.5 |
|---|---|
| Number of Teeth | 24T |
| Pitch Diameter | ≈ 12 mm (0.47 in) |
| Bore Diameter | 4 / 5 / 6 / 6.35 / 7 mm (see variant options) |
| Face Width | Typically 5–8 mm (0.20–0.31 in) |
| Material | Brass |
| Pressure Angle | 20° (standard) |
| Gear Type | Spur (straight tooth) |
| Finish | Natural brass (uncoated) |
| Pack Quantity | 1 / 2 / 5 / 10 PCS (see variant options) |
| Weight (per piece) | See variant options |
Measure your motor or drive shaft diameter with a caliper. Select the bore that matches exactly — 4 mm, 5 mm, 6 mm, 6.35 mm (common for 1/4 in imperial shafts), or 7 mm. A bore that is too large will cause slippage; too small cannot be pressed on without reaming. If your shaft is between sizes, choose the next size up and ream or use a set-screw collar.
Only other Mod 0.5 gears (spur gears, racks, or pinions) will mesh correctly. Module 0.5 is not interchangeable with Mod 1.0, Mod 0.8, or any other module standard. Always confirm the module of your mating gear before ordering.
Brass is suitable for low-to-medium torque applications such as RC vehicles, robotics, and light-duty actuators. It offers good machinability and corrosion resistance but is softer than steel. For high-torque or heavy-load applications, consider steel gears instead. Brass pairs well with steel pinions to reduce wear on the more expensive component.
Brass does not rust (it contains no iron), but it can oxidize and develop a patina over time when exposed to moisture and air. For most indoor mechanical applications this is cosmetic only and does not affect function. If operating in humid or outdoor environments, a light coat of machine oil or grease will preserve the surface finish.
Yes. Brass is easy to drill and tap. You can add a radial set-screw hole through the hub using a standard tap set. A flat ground on the shaft (D-shaft) combined with a set screw provides the most secure retention. Ensure the hub wall thickness is sufficient for your chosen screw size before drilling.
For a single repair or prototype, the 1 PCS option is the most economical entry point. If you are building a multi-axis system or want spares on hand, the 5 PCS or 10 PCS packs offer a lower per-unit cost. The 2 PCS pack suits paired-drive configurations where two identical gears are needed simultaneously.
A light machine oil or white lithium grease applied to the tooth faces is sufficient for most applications. Avoid heavy greases that attract dust in open-gear configurations. For RC vehicles, manufacturer-recommended gear lubricants are compatible with brass. Re-lubricate periodically based on run time and operating conditions.
