Acrylic (PMMA) is one of the most laser-friendly materials available. It engraves cleanly, cuts smoothly, and produces polished edges—especially when processed with a CO₂ laser, which acrylic naturally absorbs at 10.6 µm.
However, beginners often get confused when choosing between cast and extruded acrylic. Although they look identical, their engraving and cutting behavior is noticeably different.
This guide explains how acrylic interacts with laser energy, the differences between cast and extruded types, and how to choose the right one for your project.
Acrylic is a clear thermoplastic with high optical transmission and excellent absorption of CO₂ infrared light. When the laser beam hits the surface:
For engraving: the beam vaporizes a thin layer, producing contrast or texture.
For cutting: the beam melts and vaporizes material through the full thickness, forming a smooth, flame-polished edge.
Although both are made of PMMA, the manufacturing method creates different internal structures:
Cast Acrylic
Extruded Acrylic
In practical use:
Cast acrylic is preferred for engraving quality.
Extruded acrylic is preferred for cutting efficiency.
Cast acrylic produces high-contrast frosted results, ideal for awards, signage, photos, and detailed graphics.
Extruded acrylic engraves with little to no contrast, and can melt if overheated, making it less suited for decorative or text-heavy designs.
General CO₂ engraving settings:
Cast surface engraving: 15–25% power, high speed
Deep engraving: 25–40% power
Extruded engraving: even lower power to avoid melting
Tip: Slight positive defocus (+1 mm) can produce a cleaner white frost on cast acrylic.
Both cast and extruded acrylic cut well, but results vary:
Cast Acrylic
Extruded Acrylic
General CO₂ cutting guidelines:
3 mm: ~40–50% power
5 mm: ~60–70% power
8–10 mm: ~80–100% power
Tip: Higher frequency with lower air assist gives clearer, flame-like edges.
Acrylic is widely used across design, manufacturing, and creative industries:
Q: Which acrylic is better for engraving?
A: Cast acrylic — produces bright, frosted engravings.
Q: Which acrylic is better for cutting?
A: Extruded acrylic — faster, smoother cutting.
Q: Why does my engraving look melted?
A: Too much power or too slow speed; reduce energy density.
Q: Can I engrave and cut on the same piece?
A: Yes — always engrave first, cut second.
Q: What power is suitable for 5 mm acrylic?
A: 40–60W CO₂ laser is sufficient for clean cuts.
If your goal is beautiful engraved contrast, choose cast acrylic.
If your goal is efficient and fast cutting, choose extruded acrylic.
Both materials perform exceptionally well on a quality CO₂ laser system, provided the correct settings are used. Understanding your acrylic type—and adjusting parameters accordingly—is the key to producing clean, professional-grade results every time.