Spur Gears 1.5Mod Transmission Gear With Step 45#Steel Pinion Motor Gear 20T~30T

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Spur Gears 1.5Mod Transmission Gear With Step 45#Steel Pinion Motor Gear 20T~30T

Name: Spur Gears 1.5Mod Transmission Gear With Step 45#Steel Pinion Motor Gear 20T~30T
Brand: HomeDIYer
Price: 10.73 USD
Availability: InStock

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By HomeDIYer®

Number Of Teeths: 20T

Bore Diameters: 6mm

Step Diameters & Packing Quantity: 25mm & 1 Pcs

Price:

$10.73 USD

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In stock (500 units), ready to be shipped

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1.5 Module Spur Gears in 45# Steel — Stepped Bore Pinion Gears for Reliable Torque Transmission

When a loose-fitting gear causes backlash, vibration, or premature wear in your drive train, the root cause is almost always a mismatch between bore tolerance and shaft diameter. Makers, CNC builders, and small-machine engineers who need a drop-in stepped-bore pinion gear that locks onto the shaft without custom machining will find these 1.5 module spur gears a practical solution.

Each gear is machined from 45# medium-carbon steel, offering a balance of hardness and machinability suited to moderate-load power transmission. The stepped bore design provides a positive axial shoulder for shaft positioning. Tooth counts range from 20T to 30T, bore diameters from 6 mm (0.236 in) to 15 mm (0.591 in), and step outer diameters of 25 mm (0.984 in), 30 mm (1.181 in), or 35 mm (1.378 in), covering a wide range of shaft and housing combinations.

Typical use cases include DIY CNC router Z-axis drives, small conveyor reduction stages, 3D printer extruder gear trains, and tabletop robotic arm joints — anywhere a compact 1.5 mod stepped pinion gear for motor shaft is needed to transmit torque cleanly at low-to-medium speeds.

⚙️ Compatibility: Designed for 1.5 module gear systems. Mates with any standard 1.5 mod spur or helical rack. Verify bore diameter and step diameter against your shaft and housing before ordering.

✅ Key Features of These 1.5 Module Stepped Bore Spur Gears

🔩45# Medium-Carbon Steel Construction — Machined from 45# steel for a solid combination of tensile strength and wear resistance under cyclic loading in power-transmission applications.
📐Stepped Bore for Positive Shaft Seating — The integrated step shoulder provides a precise axial reference face, reducing the need for additional collars or spacers when mounting on a motor shaft.
⚙️1.5 Module Tooth Profile — Standard 1.5 mod involute tooth geometry ensures smooth meshing with any compatible 1.5 mod mating gear, rack, or pinion in your drivetrain.
📏Wide Variant Range — Available in 20T, 24T, 25T, and 30T tooth counts with bore diameters from 6 mm to 15 mm and step diameters of 25 mm, 30 mm, or 35 mm to suit diverse shaft and housing configurations.
🔄Multi-Pack Options — Choose 1, 3, or 5 pieces per order to stock spares for maintenance or build multiple identical axes in a single purchase.
🛠️Machinable for Custom Keyways — 45# steel responds well to secondary machining, allowing you to cut a keyway or set-screw flat if your application requires a keyed shaft connection.

📐 Technical Specifications — 1.5 Module Spur Gears

Module	1.5
Material	45# Medium-Carbon Steel
Tooth Count (T)	20T / 24T / 25T / 30T (see variant options)
Bore Diameter	6 mm / 6.35 mm / 7 mm / 8 mm / 10 mm / 12 mm / 14 mm / 15 mm (see variant options)
Step Outer Diameter	25 mm / 30 mm / 35 mm (see variant options)
Pressure Angle	20°
Tooth Profile	Standard Involute
Surface Finish	See variant options
Packing Quantity	1 Pcs / 3 Pcs / 5 Pcs (see variant options)
Weight (per piece)	See variant options

❓ Frequently Asked Questions

How do I choose the right tooth count for my application?

Tooth count determines the gear ratio when paired with a mating gear. A 20T pinion meshing with a 40T gear gives a 2:1 reduction. For higher torque output choose a lower tooth count (20T or 24T); for higher speed with less torque reduction choose 25T or 30T. Always match the module (1.5) of both gears.

Which bore diameter should I select for my motor shaft?

Select the bore diameter that matches your motor or drive shaft diameter. Common motor shaft sizes are 6 mm, 6.35 mm (1/4 in), 8 mm, and 10 mm. If your shaft is slightly undersized, a set-screw or keyway can compensate; if oversized, the gear will not fit without re-boring.

What does the step diameter dimension refer to?

The step diameter (25 mm, 30 mm, or 35 mm) is the outer diameter of the shoulder section machined into the gear hub. This shoulder seats against a housing bore or bearing face to provide axial location. Choose the step diameter that matches your housing or bearing inner race diameter.

How strong are these gears under load?

45# steel has a typical tensile strength of approximately 600–800 MPa after normalizing. For light-to-medium duty applications such as CNC routers, 3D printers, and small robotic joints, these gears provide adequate strength. For heavy industrial loads or continuous high-torque operation, consider hardened or alloy-steel alternatives.

Are these gears corrosion resistant?

45# carbon steel has limited inherent corrosion resistance. For indoor or dry environments this is generally acceptable. If your application involves moisture, coolant, or outdoor exposure, apply a light machine oil coating or consider a zinc-plated or stainless-steel alternative gear.

Can I use these gears with a rack and pinion system?

Yes. These 1.5 module spur gears will mesh correctly with any standard 1.5 mod gear rack. This makes them suitable for linear motion systems such as CNC gantry axes, camera sliders, and automated drawer mechanisms. Ensure the rack module is also 1.5 and the pressure angle is 20°.

Why should I order a multi-pack instead of a single piece?

Multi-packs (3 Pcs or 5 Pcs) are cost-effective when building machines with multiple identical axes, stocking maintenance spares, or prototyping gear ratio options. The per-unit cost decreases with larger packs, and having spares on hand minimises downtime if a gear needs replacement.

🛒 Select your tooth count, bore diameter, and step diameter & packing quantity above, then add to cart.

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These o rings are a great for my ear tunnels

These o rings are a great for my ear tunnels, always loosing one here and there, I always have a new ones in the drawer. Being silicone, don't have any reactions compared to standard rubber ones I purchased at hardware stores, plus much less expensive. Purchased 16mm I'd to use on 19mm tunnels, and stay on great, might be able to get away with 17mm rings, but really happy with my choice.

Will never order from these folks again

I waited a long time and that’s all I received was the eyebolt with no threaded rod attached to it

Perfect they are really made well and I used them for my car

Perfect they are really made well and I used them for my car. The only thing I had a great for us. It took three weeks to get here. So shipping was slow.

did not include wing nuts

Hi Scott, thank you for your feedback. We're sorry for any inconvenience caused. Please get in touch with us directly, and we'll assist you. Thanks for shopping with HomeDIYer!

Haven't received the order yet! It's been over

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Spur Gears 1.5Mod Transmission Gear With Step 45#Steel Pinion Motor Gear 20T~30T

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Description

1.5 Module Spur Gears in 45# Steel — Stepped Bore Pinion Gears for Reliable Torque Transmission

✅ Key Features of These 1.5 Module Stepped Bore Spur Gears

📐 Technical Specifications — 1.5 Module Spur Gears

❓ Frequently Asked Questions

Spur Gears 1.5Mod Transmission Gear With Step 45#Steel Pinion Motor Gear 20T~30T

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