1 Mod 37-39 Teeth Spur Gears Transmission Gear With Step Motor Pinion Gears

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1 Mod 37-39 Teeth Spur Gears Transmission Gear With Step Motor Pinion Gears

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Choose Model: 1M 37T

Bore: 8mm (Stainless Steel)

Packing Quantity: 1 pcs

Price:

$30.59 USD

Stock:

In stock (500 units), ready to be shipped

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1 Mod 37–39 Teeth Spur Gears — Precision Transmission for Stepper Motor Pinion Drives

When your stepper motor drive train slips, skips, or strips under load, the culprit is almost always a mismatched or worn pinion gear. Engineers, robotics builders, and CNC hobbyists who need reliable torque transfer at 1 Module pitch turn to these 37–39 tooth spur gears to keep their automation projects running without interruption.

Each gear is machined to a 1 Module (1M) tooth profile and is available in three tooth counts — 37T, 38T, and 39T — covering a range of gear ratios for fine-tuned speed and torque control. Bore options span 6 mm to 20 mm (approximately 0.24" to 0.79"), with standard round bores, keyway bores (e.g., 3×1.4 mm, 4×1.8 mm, 5×2.3 mm, 6×2.8 mm), and D-bore configurations. Material choices include standard steel, stainless steel, and blue nylon, letting you match the gear to your environment and load requirements.

Typical use cases include stepper motor pinion assemblies for 3D printers and CNC routers, gear-reduction stages in robotic arm joints, and light-duty conveyor or indexing mechanisms where a 1M pitch spur gear with a precise bore fit is essential for zero-backlash power transmission.

⚙️ Compatibility: Designed for 1 Module (1M) pitch gear systems. Mates with any standard 1M rack, pinion, or mating spur gear. Verify shaft diameter and keyway dimensions against your variant selection before ordering.

✅ Key Features of These 1 Mod Spur Gears

🦷

Three Tooth Counts

Available in 37T, 38T, and 39T to dial in your exact gear ratio for speed or torque optimization.

🔩

Wide Bore Range

Round bores from 6 mm to 20 mm (≈0.24"–0.79"), plus keyway and D-bore options for positive shaft engagement.

🛡️

Multiple Material Options

Standard steel for general use, stainless steel for corrosion-prone environments, and blue nylon for lightweight or low-noise applications.

📐

1 Module Pitch Standard

Conforms to the ISO 1 Module tooth profile, ensuring interchangeability with any standard 1M mating gear or rack.

📦

Flexible Pack Quantities

Order 1, 3, or 5 pieces per pack — ideal for prototyping, small-batch builds, or stocking spares for ongoing projects.

⚡

Stepper Motor Ready

Bore sizes and keyway profiles are selected to match common NEMA 17, NEMA 23, and similar stepper motor shaft dimensions for direct pinion mounting.

📐 Technical Specifications — 1 Mod Spur Gears

Module	1M (1 Module)
Tooth Count	37T / 38T / 39T (see variant options)
Bore Diameter	6 mm – 20 mm (see variant options)
Bore Type	Round, Keyway (3×1.4 mm / 4×1.8 mm / 5×2.3 mm / 6×2.8 mm), D-Bore (see variant options)
Material	Standard Steel / Stainless Steel / Blue Nylon (see variant options)
Pressure Angle	20° (standard spur gear)
Pitch Diameter	37 mm / 38 mm / 39 mm (= Module × Teeth)
Packing Quantity	1 pcs / 3 pcs / 5 pcs (see variant options)
Application	Stepper motor pinion, CNC drive train, robotic joint, conveyor indexing

❓ Frequently Asked Questions

How do I choose between 37T, 38T, and 39T?

The tooth count determines your gear ratio when paired with a pinion or mating gear. More teeth on the driven gear = lower output speed but higher torque. For most NEMA 17 stepper pinion setups, 37T–39T gears are used in the first reduction stage. Choose based on the ratio your application requires; the difference between these three counts is small and mainly affects fine-tuning of speed.

Which bore size should I select for my stepper motor shaft?

Measure your motor shaft diameter precisely with calipers. Common NEMA 17 shafts are 5 mm; NEMA 23 shafts are typically 6.35 mm or 8 mm. Select the bore that matches your shaft. If your shaft has a flat (D-cut) or keyway, choose the corresponding D-bore or keyway variant to prevent rotation slip under load.

What is the difference between the standard, stainless steel, and blue nylon versions?

Standard steel gears offer good strength for general indoor automation. Stainless steel gears resist corrosion and are suited for humid, washdown, or outdoor-adjacent environments. Blue nylon gears are lighter, run quieter, and are self-lubricating — ideal for low-load, noise-sensitive, or weight-critical applications. Nylon gears have lower load capacity than metal variants.

Are these gears compatible with standard 1M racks and pinions?

Yes. These gears conform to the ISO 1 Module (1M) tooth profile with a standard 20° pressure angle, making them interchangeable with any 1M-pitch rack, pinion, or mating spur gear from any manufacturer that follows the same standard.

How strong are these gears under continuous load?

Load capacity depends on material and tooth count. Steel and stainless steel variants handle moderate-to-high continuous torque typical of CNC and robotics applications. Nylon variants are suited for lighter, intermittent loads. For precise load ratings, refer to your application's torque requirements and compare against standard 1M gear load tables for the chosen material.

Can I use these gears outdoors or in wet environments?

Stainless steel variants are the best choice for damp or corrosion-prone environments. Standard steel gears should be kept dry or lubricated to prevent rust. Blue nylon gears resist moisture well but are not rated for full submersion. For outdoor use, stainless steel is recommended.

Do I need to buy a set, or can I order a single gear?

You can order as few as 1 piece per variant. The 3-pcs and 5-pcs pack options offer a lower per-unit cost and are convenient for builds requiring multiple identical gears or for keeping spares on hand.

🛒 Select your model (tooth count), bore size, and packing quantity above, then add to cart.