Polished thermally bent clear acrylic bracket
Polished thermally bent clear acrylic bracket
Cast vs Extruded Acrylic: Mechanical, Optical, Chemical and Weathering Data for PMMA Selection
This page compares cast and extruded PMMA and structures the mechanical, optical, chemical and weathering data you need to choose one for your part. We cast our own cast acrylic sheet (branded Calypto) and machine it in the same facility; for the fabrication-side decision — which machines, laser-cuts and thermoforms better — see cast vs extruded for fabrication.
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Machined cast acrylic bracket with polished edges
No value is claimed without the grade datasheet; each row states company guidance versus order-specific data.
Company-declared
The selection guidance we apply
Cast acrylic recommended for machining-heavy parts, extruded for flat sheet: that is the selection guidance we apply when quoting, and the quote states which form was assumed for your application.
Both forms in the fabrication range
We fabricate both forms. Fabricated acrylic thickness range 3–100 mm applies to machined, formed and finished parts, and standard sheet stock range 1–30 mm covers common sheet orders; availability depends on grade, colour and source. Cast acrylic sheet is produced on our own Suzhou casting line and supplied as Calypto cast acrylic; Mitsubishi or Lucite optical-grade PMMA is supplied when the order specifies a branded material.
Property data confirmed per order
Mechanical, optical, chemical and weathering data are grade-specific. This page does not publish values: the property tables below show which data families are confirmed per order from the grade datasheet, and the quote names the grade assumed for your application.
Annealing for both forms
Machined parts annealed with the cast-acrylic industry-standard schedule. Annealing reduces but does not eliminate crazing or stress-cracking risk in either form, so service conditions are reviewed per application.
Line-bent acrylic bracket formed from sheet
Line-bent acrylic bracket formed from sheet
When to agree grade and finishing
When an application exposes the part to solvents, oils, cleaning agents or outdoor weather, the grade and finishing route are agreed before quoting; chemical resistance and weathering behaviour are not claimed generically for either form.
Cast versus extruded selection
| Choose this when | Do not choose this when | Option | Claim IDs |
|---|---|---|---|
| Your part is machining-heavy, bonded, thick or optical | Your part is flat, laser-cut and cost-sensitive | Cast acrylic | AF-C15 |
| Your fit is thickness-critical and consistency matters | Tight machined tolerance is the dominant requirement | Extruded acrylic | AF-C15 |
| You need a polished, glass-clear optical appearance | The part is hidden or purely functional | Cast acrylic preferred; appearance agreed per order | AF-C15 |
| You need economical flat profiles in volume | The part carries deep pockets, threads or bonded seams | Extruded acrylic | AF-C15 |
| The part meets solvents, oils or outdoor weather | No chemical or weathering exposure is expected | Grade and finishing confirmed per order before quoting | AF-C15 |
Material supply and selection conditions
| Property | Value | Unit | Product grade | Thickness specimen | Test method / standard | Evidence status | Qualification | Claim IDs |
|---|---|---|---|---|---|---|---|---|
| Selection guidance | Cast for machining-heavy parts; extruded for flat sheet | n/a | Cast and extruded acrylic | n/a | Company guidance | company-declared | Recommendation, not verified property data | AF-C15 |
| Sheet stock range | 1–30 mm | mm | Cast and extruded sheet | Standard sheet | Supplier sheet range | company-declared | Availability depends on grade, colour and source | AF-C27 |
| Fabrication thickness range | 3–100 mm | mm | Cast and extruded acrylic | Fabricated parts | Company statement | company-declared | Cast versus extruded ranges pending | AF-C05 |
| Sheet source | Calypto cast acrylic, cast in our own Suzhou facility; Mitsubishi or Lucite optical-grade PMMA on request | n/a | Cast acrylic | Sheet supply | Production and purchasing records per order | company-declared | Branded material supplied when the order specifies it | AF-C21 |
| Annealing after machining | Cast-acrylic industry-standard schedule | n/a | Machined parts, both forms | Order-specified | Company process statement | company-declared | Reduces but does not eliminate cracking risk | AF-C10 |
Mechanical property data – availability by grade
| Property | Value | Unit | Product grade | Thickness specimen | Test method / standard | Evidence status | Qualification | Claim IDs |
|---|---|---|---|---|---|---|---|---|
| Tensile strength and modulus | Confirmed from the grade datasheet at order time | n/a | Order-specified cast or extruded grade | Datasheet specimen | Supplier datasheet method | order-specific | Not claimed without the datasheet | |
| Flexural properties | Confirmed from the grade datasheet at order time | n/a | Order-specified cast or extruded grade | Datasheet specimen | Supplier datasheet method | order-specific | Not claimed without the datasheet | |
| Impact resistance | Confirmed from the grade datasheet at order time | n/a | Order-specified cast or extruded grade | Datasheet specimen | Supplier datasheet method | order-specific | Not claimed without the datasheet | |
| Hardness and machinability | Machining behaviour described per order in DFM | n/a | Cast and extruded acrylic | Order-specified | Company DFM review | company-declared | Selection guidance, not verified data | AF-C15 |
Optical property data – availability by grade
| Property | Value | Unit | Product grade | Thickness specimen | Test method / standard | Evidence status | Qualification | Claim IDs |
|---|---|---|---|---|---|---|---|---|
| Light transmission | Target agreed per order; measured by the agreed method when specified | n/a | Order-specified grade | Specified specimen thickness | Agreed measurement method | order-specific | No value published here without measurement evidence | |
| Haze | Target agreed per order; measured by the agreed method when specified | n/a | Order-specified grade | Specified specimen thickness | Agreed measurement method | order-specific | No value published here without measurement evidence | |
| Optical clarity | Appearance described as clear / glass-clear / optically clear | n/a | Cast and extruded acrylic | Order-specified | Master sample per order | company-declared | Defined against the approved master sample; no numeric claim | AF-C16 |
Chemical resistance data – availability by grade
| Property | Value | Unit | Product grade | Thickness specimen | Test method / standard | Evidence status | Qualification | Claim IDs |
|---|---|---|---|---|---|---|---|---|
| Solvent and oil resistance | Grade-specific; compatibility confirmed per order against the grade datasheet | n/a | Order-specified grade | Datasheet specimen | Supplier datasheet method | order-specific | Not claimed generically for either form | |
| Cleaning agent compatibility | Confirmed per order for the proposed cleaning agents | n/a | Order-specified grade | Order-specified | Supplier datasheet method | order-specific | Confirmed per order | |
| Stress cracking under solvent contact | Annealing reduces but does not eliminate risk | n/a | Machined parts, both forms | Order-specified | Company process statement | company-declared | Solvent exposure reviewed per application | AF-C10 |
Weathering data – availability by grade
| Property | Value | Unit | Product grade | Thickness specimen | Test method / standard | Evidence status | Qualification |
|---|---|---|---|---|---|---|---|
| UV and outdoor weathering | Grade-specific; outdoor applications reviewed per order | n/a | Order-specified grade | Datasheet specimen | Supplier datasheet method | order-specific | No weathering claim without the datasheet |
| Colour stability | Confirmed per order for the selected grade and colour | n/a | Order-specified grade | Order-specified | Supplier datasheet method | order-specific | Confirmed per order |
| Service temperature | Confirmed per order for the selected grade | n/a | Order-specified grade | Order-specified | Supplier datasheet method | order-specific | Thermal limits confirmed per order |
Evidence and verification
- Grade datasheets, material certificates and the two supplier reference PDFs are supplied on request per order; supplier PDFs are external references, not Hongyee finished-part evidence.
- A certificate of conformity or batch COA can be supplied per order on request.
- Material sourcing and selection statements on this page are company-declared by AcrylicFabWorks unless stated otherwise.
- Applicable product grade: Cast and extruded acrylic (PMMA), grade confirmed per order
- Fact owner: Engineering and quality review, AcrylicFabWorks
- Last reviewed: 2026-08-27
FAQ
Which is better for CNC machining, cast or extruded acrylic?
For machining-heavy parts we recommend cast acrylic: it machines cleaner with lower internal stress and less chipping, which is why precision machined parts are typically specified in cast material.
When should I choose extruded acrylic?
Choose extruded for economical flat work, laser-cut profiles and thickness-critical fits where consistency and cost matter more than tight machined tolerance; the quote states which grade was assumed and why.
Do you publish mechanical, optical, chemical or weathering values?
No values are published without the grade datasheet: each property family is confirmed per order for the exact grade, thickness and colour, and supplied on request with the quote.
Do you use Mitsubishi acrylic?
Cast acrylic sheet is cast in-house and supplied as Calypto; Mitsubishi or Lucite optical-grade PMMA is supplied when the order specifies a branded material. Both are company-declared statements, and production or purchasing records are available on request per order.
Which thicknesses are available?
Standard acrylic sheet stock range 1–30 mm covers common sheet orders and fabricated parts run 3–100 mm; actual availability depends on grade, colour and source and is confirmed at ordering.
Why do some acrylic parts machine better than others?
Cast acrylic is recommended for machining-heavy parts because it machines cleaner and holds edges better, while extruded sheet suits flat parts with simple geometry. The difference shows in edge quality, machining stability and consistency; the quote states which form was assumed for your application.
Which acrylic form should I specify for an outdoor application?
Weathering and chemical behaviour are grade-specific and not claimed generically for either form. When the part sees solvents, oils, cleaning agents or outdoor weather, the grade and finishing route are agreed before quoting, and property data is confirmed per order from the grade datasheet.
What property data should a supplier provide for acrylic selection?
Mechanical, optical, chemical and weathering data are grade-specific; the selection page does not publish values, and the quote names the grade assumed for your application. When needed, targets and method are confirmed per order and reported with the first article or batch.
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