These plastic gears are lighter and quieter than metal gears—pair them with metal worms for lubrication-free operation. 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, pitch/module, number of thread starts, and thread direction.

Speed ratio is the ratio by which output shaft speed is reduced. As speed decreases, torque increases.

Acetal gears are lightweight, and resist corrosion and chemicals. They absorb less moisture than nylon gears, so they’re less prone to dimensional changes. They’re best suited for light duty applications, such as prototyping.

Nylon gears are lightweight and stronger than acetal gears.

For technical drawings and 3-D models, click on a part number.

Compared to plastic gears, these metal ratcheting gears are better for high-load, high-speed, and heavy duty applications. Used to prevent unwanted motion in jacks, tie downs, clutches, and winches, ratchet gears have sloped teeth that allow motion in one direction and prevent it in the other.

Gears with hardened teeth are more wear resistant than gears with teeth that are not hardened. Gears with teeth that are not hardened can be hardened to fit your application. Hardening a gear’s teeth increases its wear resistance.

A pawl is required to prevent backward motion.

For technical drawings and 3-D models, click on a part number.