Spur Gear C45 Steel 12 Tooth - 160 Tooth Motor Pinion Flat 1M 1.5M 2M 2.5M 3M 4M

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Spur Gear C45 Steel 12 Tooth - 160 Tooth Motor Pinion Flat 1M 1.5M 2M 2.5M 3M 4M

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Sizes: 1 Mod 85 Teeth Out Diameter 87mm

Amount: 1Pcs

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$17.65 USD

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In stock (500 units), ready to be shipped

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Spur Gear C45 Steel — Precision Motor Pinion Gears for DIY Automation & Robotics

When your motor shaft needs a reliable, dimensionally accurate mating gear, a mismatched or undersized pinion is the first point of failure. Engineers, hobbyists, and small-workshop builders who work with stepper motors, servo drives, and custom gearboxes need spur gears that hold tight tolerances across a wide size range — without sourcing from multiple suppliers. These C45 steel spur gears are machined to metric module standards and cover the most commonly requested combinations in one catalog.

Each spur gear is machined from C45 medium-carbon steel, offering a balance of machinability and load-bearing strength. The range spans Module 1, 1.5, 2, 2.5, 3, and 4, with tooth counts from 12 to 160 teeth and outer diameters from approximately 21 mm (0.83 in) up to 192.5 mm (7.58 in). Bore diameter and keyway dimensions vary by size — see variant options for exact bore specs.

Typical use cases include DIY CNC router drive trains requiring a 2M or 3M pinion gear, robotics joint actuators using small 1M or 1.5M motor pinion gears, and light industrial conveyor or indexing mechanisms where a 2.5M or 4M spur gear provides the torque multiplication needed for reliable cycle times.

⚙️ Compatibility: Designed for metric module gear systems. Mating gears must share the same module (M) value. Bore diameter varies by size — confirm bore and keyway requirements against your shaft spec before ordering.

✅ Key Features of These C45 Steel Spur Gears

🔩 C45 Medium-Carbon Steel Construction

Machined from C45 steel for solid load capacity, consistent tooth geometry, and resistance to deformation under moderate torque loads in drive and indexing applications.

📐 Wide Module & Tooth Count Range

Available in Module 1, 1.5, 2, 2.5, 3, and 4 with tooth counts from 12 to 160 — covering small motor pinions up to large reduction gears in a single product family.

📏 Metric Standard Tooth Profile

Cut to standard metric involute tooth profile, ensuring correct mesh with any same-module mating gear regardless of brand or source.

⚡ Flat (Plain) Bore Design

Flat bore style allows straightforward shaft fitting with a set screw or custom keyway machining — suitable for prototyping and production fixtures alike.

🔄 Broad OD Coverage: 21 mm – 192.5 mm

Outer diameters span from 21 mm (0.83 in) for compact motor pinions to 192.5 mm (7.58 in) for larger reduction stages, all within one consistent product line.

🛠️ Ready for DIY & Light Industrial Use

Suitable for CNC builds, robotic arms, conveyor drives, indexing tables, and educational automation rigs where standard metric gearing is required.

📐 Technical Specifications — C45 Steel Spur Gears

Material	C45 Medium-Carbon Steel
Gear Type	Spur Gear (Involute Tooth Profile)
Available Modules	1M, 1.5M, 2M, 2.5M, 3M, 4M
Tooth Count Range	12 Teeth – 160 Teeth
Outer Diameter Range	21 mm – 192.5 mm (0.83 in – 7.58 in)
Bore Type	Flat / Plain Bore
Bore Diameter	See variant options
Hub Width / Face Width	See variant options
Pressure Angle	20° (standard metric involute)
Surface Finish	See variant options
Quantity per Order	1 Piece

❓ Frequently Asked Questions

How do I choose the right module for my application?

The module (M) value must match between mating gears. Module 1 and 1.5 are common for small stepper motor pinions and light-load robotics. Module 2 and 2.5 suit medium-duty CNC and conveyor drives. Module 3 and 4 are used where higher torque transmission or larger center distances are needed. Check your existing gear or gearbox documentation for the module specification before ordering.

What is the bore diameter for each size?

Bore diameter varies by module and tooth count. Please refer to the variant options or contact us to confirm the bore diameter for your specific size before ordering, especially if you have a fixed shaft diameter requirement.

Can these gears be used outdoors or in wet environments?

C45 steel is not inherently corrosion-resistant. For outdoor or humid environments, we recommend applying a suitable lubricant or protective coating after installation. If corrosion resistance is a primary requirement, consider stainless steel or plastic gear alternatives for your application.

Are these compatible with gears from other brands?

Yes — as long as the mating gear shares the same module value and uses a standard 20° pressure angle involute tooth profile, these gears will mesh correctly regardless of brand. Always verify module, pressure angle, and face width alignment before assembly.

What is the maximum torque these gears can handle?

Torque capacity depends on the module, tooth count, face width, and operating speed. C45 steel provides moderate strength suitable for light to medium-duty applications. For high-torque or high-cycle industrial use, consult a mechanical engineer to verify the gear rating against your load requirements.

Do I need to machine the bore before use?

These gears are supplied with a flat (plain) bore. Depending on your shaft diameter, you may need to bore, ream, or add a keyway to achieve a precise fit. This is standard practice for metric spur gears used in custom drive systems. Confirm the supplied bore diameter matches or is slightly undersized relative to your shaft before machining.

Which size should I choose for a stepper motor pinion?

For NEMA 17 and NEMA 23 stepper motors, Module 1 or 1.5 gears with 12–20 teeth are the most common pinion choices. For higher-torque NEMA 34 applications, Module 2 or 2.5 with 15–25 teeth is typical. Always match the module to your driven gear and verify the bore fits your motor shaft diameter.

🛒 Select your module and tooth count 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

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

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Spur Gear C45 Steel 12 Tooth - 160 Tooth Motor Pinion Flat 1M 1.5M 2M 2.5M 3M 4M

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Description

Spur Gear C45 Steel — Precision Motor Pinion Gears for DIY Automation & Robotics

✅ Key Features of These C45 Steel Spur Gears

📐 Technical Specifications — C45 Steel Spur Gears

❓ Frequently Asked Questions

Spur Gear C45 Steel 12 Tooth - 160 Tooth Motor Pinion Flat 1M 1.5M 2M 2.5M 3M 4M

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