Acetal Sheet — Thicknesses, Sizes & Stock Forms
Acetal sheet is flat stock produced from polyoxymethylene (POM), an engineering thermoplastic combining low friction, high stiffness, and outstanding dimensional stability. These characteristics make acetal sheet a reliable choice for fabricated wear pads, slide plates, pump components, and precision flat parts that require tight thickness tolerances and consistent mechanical performance.
At a glance:
- Thickness range: 0.125" to approximately 4.0" (standard stock)
- Standard sheet sizes: 24" × 48" and 48" × 96"
- Thickness tolerance: close commercial tolerances
- Material: Polyoxymethylene (POM) — acetal family
- Color: Natural (white/off-white); black available
- Low moisture absorption — stable in humid and wet environments
Standard Thickness Table
Acetal sheet is stocked in common thicknesses for saw, router, and waterjet fabrication:
| Thickness | Sheet Sizes | Notes |
|---|---|---|
| 1/8" (0.125") | 24"×48", 48"×96" | Thin wear liners, shims |
| 1/4" (0.250") | 24"×48", 48"×96" | Slide plates, guides |
| 3/8" (0.375") | 24"×48", 48"×96" | Structural flat parts |
| 1/2" (0.500") | 24"×48", 48"×96" | Wear pads, valve bodies |
| 3/4" (0.750") | 24"×48", 48"×96" | Heavier structural sections |
| 1" (1.000") | 24"×48", 48"×96" | Machined flat components |
| 2" (2.000") | 24"×48" | Thick block applications |
Non-standard thicknesses and cut-to-size pieces available. Contact Ready Plastics for current stock and custom cut options.
Mechanical Properties
| Property | Value |
|---|---|
| Density | 1.49 g/cm³ |
| Water absorption (24 h / 96 h) | 0.05 / 0.1 % |
| Flammability (UL 94) | HB |
| Heat deflection temp. (HDT, Method A) | 141 °C / 285 °F |
| Service temp. (long term) | 110 °C / 230 °F |
| Service temp. (short term) | 150 °C / 300 °F |
| Tensile strength | 53 MPa / 7,600 psi |
| Tensile modulus | 3,000 MPa / 435,000 psi |
| Flexural strength | 85 MPa / 12,000 psi |
| Flexural modulus | 3,000 MPa / 435,000 psi |
| Shore D hardness | 81 |
Typical Applications
Acetal sheet is cut, routed, or machined into flat components requiring low friction and dimensional accuracy:
- Wear pads and slide plates — resists abrasion in conveyor and automation systems
- Pump housings and valve body blanks — chemical resistance supports fluid-handling environments
- Fixture and jig plates — dimensional stability supports precision assembly tooling
- Food processing guides — FDA-compliant grades available for food-contact applications
- Electrical spacers and insulators — electrically non-conductive baseline grade
- Structural flat parts — high stiffness-to-weight ratio in general fabrication
Machining Acetal Sheet
Acetal sheet saws, routes, and waterjets cleanly with standard equipment. Carbide-tipped saw blades and single-flute or O-flute router bits produce smooth edges with minimal heat buildup. For milled pockets and bored holes, standard HSS or carbide end mills work well at moderate speeds. Acetal does not require annealing prior to machining; however, stress-relieve thick sections at moderate temperature after rough machining if critical flatness is required.