Best Practices For Surface Engraving Cast Acrylic

Best Practices For Surface Engraving Cast Acrylic

Acrylic is an awesome medium for C02 lasing. This article will cover the processing of acrylic for edge-lit projects but these principles still apply to basic acrylic etching in general. Before we jump in let's cover a few important details.



There are 2 common variations of acrylic and while they are all chemically similar, they behave very differently from one another due to the manufacturing process:



  • Extruded Acrylic: This is what is commonly found in big box and local hardware stores. This is made by forcing the acrylic resin through a form. This type is usually masked in plastic and when etched produces very little contrast.
  • Cast Acrylic: This type of acrylic is not commonly found locally but it is used in aquariums so a pet or aquatics store may be worth a try. It is produced by pouring the resin in a cast and subjecting it to heat and pressure. Cast is usually masked with thin craft paper but not always. Cast is great for etching and produces remarkable contrast.

You can learn more about the differences between cast and extruded HERE.


It is called edge lit  because light enters one or more edges of the substrate by using ambient light or a light source such as an led array. Once the light is inside the material, it travels throughout the entire volume of the material.

The acrylic-to-air boundary surfaces create internal reflectivity that keeps much of the light inside the material ( like when you are under water and the surface looks mirrored from below) and it is diffused over a wide area. Etching the acrylic allows the light to escape at the ablated areas and causes the engraved area to glow.


When engraving you  usually only want enough power to sustain a uniform beam signature and to barely ablate the substrate however variable depth engraving (3D relief) can produce some interesting and desirable effects.


When you cut acrylic there are a lot of factors at play besides your speed, power, focus, etc... Russ Sadler has some great in-depth tutorials on one of his YouTube channels HERE.


Please check the Materials, Power, & Speed Settings articles for more specific information on settings HERE.

    • Related Articles

    • 3D Relief Engraving on Acrylic

      Here is a 3D Relief engraving workflow on acrylic.  This is the same file we used on the wood 3d relief engraving: 3D Relief Engraving On Natural Wood The acrylic is 6"x 6" x0.75" cast. Thunder Nova 35-80, stock 2" lens, standard focus (6mm from ...
    • Best Practices For Engraving Glass

      typically you want to use as little power as possible to make a mark... kinda like when doing edge lit acrylic...  the laser beam doesn't actually ablate the glass, it creates microfractures in the glass when the water molecules are converted to ...
    • Best Practices for Fill Layer Engraving and what settings to watch out for

      This article covers some Best Practices for Fill Layer settings that are commonly used, misused or unknowingly used. Fill Layer Basic Settings: Speed: Speed at which the laser head moves in the Engrave Direction based off the Scan Angle. Max Power: ...
    • Best Practices for using Auto Focus on a Nova Series Machine

      This article covers the best practices for using Auto Focus on your Nova Series machine. When to NOT use Auto Focus: 1. Rotary jobs - The shape of the rotary machine and tumblers do not work with the sensors 2. If not using the stock 2" head. Auto ...
    • Best Practices For Utilizing Remote Support

      This is a crash course on how to navigate the resources available as well as get your issue resolved in the most efficient, expeditious manner. Here are the best practices for getting effective support: Thunder Laser Warranty Issues If your Thunder ...