Tolerances & specifications
What to expect from cast acrylic tubes and rods — dimensional tolerances, material properties, and certification.
Certification
All material sold by American Acrylic Works is manufactured by US Cast in Pittsgrove, NJ and certified to ASTM D5436 Type UVA, Finish 1. Every order ships with a certificate of conformance referencing the specific cast batch your material came from — see our credentials page for details.
Dimensional tolerances — Tubes
Cast acrylic tubes are formed in cylindrical molds. Tolerances are typical for cell-cast production:
| Dimension | Tolerance |
|---|---|
| Outside diameter (OD) | +0.000″ / −0.020″ (nominal to slightly under) |
| Wall thickness | ±10% of nominal wall |
| Length (as cut) | +0.125″ / −0.000″ (cut slightly long, never short) |
| Straightness | ≤ 0.050″ per foot of length |
| Ovality | OD within tolerance at any cross-section |
Note on wall thickness: Cast tubes may have slight wall variation around the circumference. This is inherent to the casting process and is within ASTM D5436 allowances. If your application requires uniform wall thickness to tighter tolerances, the tube can be machined (turned on a lathe) after casting.
Dimensional tolerances — Rods
| Dimension | Tolerance |
|---|---|
| Diameter | +0.000″ / −0.015″ (nominal to slightly under) |
| Length (as cut) | +0.125″ / −0.000″ |
| Straightness | ≤ 0.030″ per foot of length |
| Roundness | Diameter within tolerance at any cross-section |
Material properties
| Property | Value | Test method |
|---|---|---|
| Density | 1.19 g/cm³ (0.043 lb/in³) | ASTM D792 |
| Light transmission | 92% | ASTM D1003 |
| Tensile strength | 10,000 psi (69 MPa) | ASTM D638 |
| Flexural modulus | 450,000 psi (3.1 GPa) | ASTM D790 |
| Impact strength (Izod) | 0.4 ft·lb/in | ASTM D256 |
| Heat deflection temp | 198°F (92°C) at 264 psi | ASTM D648 |
| Max continuous service temp | 180°F (82°C) | — |
| Water absorption (24hr) | 0.3% | ASTM D570 |
| Refractive index | 1.49 | ASTM D542 |
Surface finish
As-cast surfaces have a smooth, glossy finish (Finish 1 per ASTM D5436). Cut ends are saw-cut and may show minor tooling marks. Flame polishing or buffing can restore optical clarity to cut surfaces.
Chemical resistance
Cast acrylic resists:
- Most aqueous solutions — water, saline, dilute acids, dilute bases
- Mineral oils and many food-grade lubricants
- UV radiation — no yellowing or degradation over time
Cast acrylic is not resistant to:
- Ketones (acetone, MEK) — will dissolve or craze the surface
- Chlorinated solvents (methylene chloride, chloroform)
- Aromatic hydrocarbons (toluene, xylene)
- Strong alcohols at high concentration
Need tighter tolerances?
If your application requires tighter dimensional control than standard casting tolerances, we can machine tubes and rods to your specification. Contact us with your requirements for a quote.