Delrin vs UHMW

Delrin and UHMW are both popular machinable plastics, but they behave very differently. Delrin is rigid and precise; UHMW is tough, slippery, and forgiving.

Property undefined undefined
Stiffness (modulus) High, 3.1 GPa Low, 0.7 GPa
Strength Higher Lower
Wear / abrasion Good Excellent
Impact resistance Good Excellent
Friction Low Very low
Dimensional stability Excellent Fair, can creep
Density 1.41 g/cc 0.93 g/cc
Typical use Precision gears, bushings Wear strips, liners, chutes

Which should you choose

Choose Delrin for rigid, dimensionally stable parts that need tight tolerances, such as gears, cams, and precision bushings.

Choose UHMW for abrasion and impact surfaces where toughness and a low-friction face matter more than stiffness, such as wear strips and chute liners.

Precision versus toughness. Delrin holds tight tolerances and stays rigid. UHMW shrugs off impact and abrasion but flexes and creeps, so it is not for precision parts.

Compare data sheets: Delrin (Acetal) and UHMW.

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