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True Precision Machining

Material datasheet · Engineering thermoplastic

Acetal Homopolymer (Polyoxymethylene)

UNS — · Stress-relieved extruded rod/plate; cast for thick sections

The general-purpose engineering plastic. Strong, stiff, low-friction, easy to machine.

UTS
10.1 ksi
70 MPa
Yield strength
10.1 ksi
70 MPa
Elongation
25%
in 2″
Hardness
HRR 120 / Shore D 86
Typical
Density
0.051
lb/in³ · 1.42 g/cc
Modulus E
0.5
Mpsi · 3.1 GPa
CTE
61.1
µin/in·°F
Service T (max)
200°F
Continuous

Chemical composition

Nominal % by weight.

Element % by wt
C, H, O (acetal homopolymer)

Applicable specifications

AMS / ASTM / MIL.

  • ASTM D6100 (Group 1)
  • DuPont Delrin 150
  • FDA-compliant grades available

Machining guidance

CNC parameters and tooling.

Roughing SFM
300–600
Finishing SFM
400–800
Machinability rating
80 / 100
B1112 = 100
Coolant
Air blast; light coolant for finishing
Tooling

Polished carbide; sharp positive rake; HSS works for low-volume

Notes

Watch for residual stress in extruded stock — can warp post-machining. Specify stress-relieved bar for tight-tolerance work.

Stock & cost

Forms and Q1 2026 pricing.

Available forms
Round barPlateSheetTube
Stock cost
$5.00–$10.00/lb
Mid-quantity bar/plate, Q1 2026 USD
Common finishes
  • Bead blast (matte)
  • Color (purchased pigmented)

Typical applications

Where Delrin / POM is the right pick.

  • Gears
  • Cams
  • Bushings
  • Snap-fits
  • Valve seats
  • Conveyor components

Alternative materials

Substitute or upgrade options.

  • Acetal copolymer (better hot water)
  • Nylon (impact resistance)
  • PEEK (high T)

True Precision Machining · Buellton, CA

Machine your part in Delrin / POM.

5-axis CNC · ISO 9001 · AS9100 · ITAR · CMMC-compliant · DFARS-compliant supply chain. AS9102 FAI on aerospace.

Phone: 805-964-4545
Email: info@trueprecisionmachining.com
Web: trueprecisionmachining.com
Datasheet generated 2026 · Mechanical values are typical room-T averages from MMPDS / ASM. Verify against MTRs for design-critical applications.

Technically reviewed by the True Precision Machining engineering team · Last reviewed June 2026

Standards referenced: ASTM D6100 (Group 1), DuPont Delrin 150, FDA-compliant grades available