PS30/21B-12 Metric Glass Filled Nylon Spur Gear 21 Tooth 3 Mod Pilot Bored 12mm

Metric Glass Filled Nylon Spur Gears: Spur gears are one of the most common type of gears. They have straight teeth and are generally mounted on parallel shafts. They are designed to exchange speed for torque or vice-versa between input and output shafts, dependent on the gear ratios chosen they can step-up / down the output speed or torque.
Lubrication: In most cases where Glass Filled Nylon gears are deployed no lubrication is required especially if used in conjunction with a steel opposite gear, the material has self lubricating properties. They are suited to running directly on the shaft with no additional bearings required providing the surface hardness of the shaft is suitable, increased surface hardness will extend bearing life. Soft steels, stainless steels and none ferrous metals will not perform well as a bearing surface for glass-filled nylon products. Glass filled nylon gears are well suited to dusty or washdown environments, although excessive contamination will reduce service life notably.
Material: Manufactured from 30% Glass-Filled Nylon 6 to increases tensile strength, stiffness and compression strength. Glass-filled Nylon offers better strength than general-purpose Nylon. It is a tough, durable material and is readily machineable.
Benefits: High quality, good tensile strength, pre-bored to a nominal undersize bore to allow finish machining as required, high quality off the shelf component.
Gear Geometry and Modulus or Mod: The reality of gear geometry and modulus is it can become quite complicated but the rule of thumb is to only use gears of the same modulus together.
The modulus of a gear is a ratio calculated from the gear diameter at half its tooth height divided by the number of teeth, gear modulus must be the same between connecting gears in a drive train, bigger mod ratios have fewer teeth and will transfer larger amounts of power, smaller mod ratios will tend to be in faster and quieter applications.