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Metal Worms and Worm Gears

Worm gears use screw threads to make large reductions to shaft speed while transmitting motion at a right angle. They transmit motion from worm to gear and cannot be reversed. For gears and worms to mesh correctly, they must have the same pressure angle and pitch/module. These worms are compatible with plastic worm gears.
Speed ratio is the ratio by which output shaft speed is reduced. As speed decreases, torque increases.
4140 alloy steel worms are already mounted on a shaft, so they’re ready to use with no machining required. The threads are ground into the shaft for higher precision than rolled threads, and hardened for additional durability and precision.
For technical drawings and 3-D models, click on a part number.

Shaft | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Module | Pressure Angle | Worm Lg., mm | Gear Pitch Dia., mm | OD, mm | Dia., mm | Lg., mm | Number of Thread Starts | Thread Direction | Teeth Heat Treatment | Teeth Fabrication | Each | |
4140 Alloy Steel | ||||||||||||
0.5 | 20° | 12 | 9 | 10 | 6 | 65 | 1 | Right Hand | Hardened | Ground | 000000000 | 000000 |
0.5 | 20° | 12 | 9 | 10 | 6 | 65 | 2 | Right Hand | Hardened | Ground | 000000000 | 00000 |
0.8 | 20° | 20 | 12 | 14 | 8 | 85 | 1 | Right Hand | Hardened | Ground | 000000000 | 00000 |
0.8 | 20° | 20 | 12 | 14 | 8 | 85 | 2 | Right Hand | Hardened | Ground | 000000000 | 000000 |
1 | 20° | 30 | 16 | 18 | 18 | 140 | 1 | Right Hand | Hardened | Ground | 000000000 | 000000 |
1.5 | 20° | 40 | 25 | 28 | 26 | 190 | 1 | Right Hand | Hardened | Ground | 000000000 | 000000 |