When designing a gear system, one of the first choices is material: plastic or metal? POM (Delrin) gears have become increasingly popular as a cost-effective alternative to metal gears in many applications. This comparison covers performance, cost, and application fit.

POM Gear vs Metal Gear: Head-to-Head

PropertyPOM (Delrin) GearSteel GearAluminum Gear
Weight1.41 g/cm³7.85 g/cm³2.7 g/cm³
Noise LevelLowHighMedium
LubricationSelf-lubricatingRequiredRecommended
Cost per Gear$$$$$$
Max Operating Temp100°C300°C+200°C
CorrosionExcellentPoor (needs coating)Good
Load CapacityMediumVery HighMedium-High
Electrical InsulationYesNoNo

When POM Gears Are the Better Choice

  • Noise-sensitive applications (office equipment, medical devices)
  • Where lubrication is impractical or undesirable
  • Cost-sensitive medium-load applications
  • Electrical isolation required between gear stages
  • Corrosive or wet environments
  • Weight reduction targets (aerospace, portable devices)

When Metal Gears Are Necessary

  • Very high torque or shock loading
  • Operating temperatures above 100°C
  • Extremely high cycle life (millions of cycles)
  • When mating with existing metal gears
  • Very high precision requirements for positional accuracy

Cost Comparison: POM vs Metal CNC Machined Gears

For a typical 50mm diameter spur gear in quantities of 100, a CNC machined POM gear costs 40-60% less than its steel equivalent. Material cost is lower and machining time is faster due to higher feed rates.

Get a quote for POM gears. ISO 9001 certified. Prototype to 10,000+ pieces.