What should be considered when cutting thick acrylic?
Our tips for laser cutting thick acrylic from 20 mm
Acrylic glass (also PMMA or Plexiglass) is used in the advertising industry or in trade show construction due to its crystal clear texture and glossy surface. Thick acrylic sheets of more than 20 mm thickness are used especially for displays or art objects. The challenge in processing is to avoid an uneven, milky or discolored cutting edge. We have summarized the most important tips for a high-quality cutting result here.
For crystal-clear cut edges, routed or sawn acrylic sheets must first be finished. This work step is omitted with laser processing. Nevertheless, a perfect result depends on many parameters:
For processing thick acrylic, our systems are equipped with laser sources from 200 to 650 watts of power. The power has direct influence on cutting quality and speed. The more power, the faster you can cut. We will work out the optimum settings for your material in our in-house application center and make them available to you.
In regular acrylic cutting, we specifically work with compressed air of varying strengths to achieve perfect results. However, when cutting thicker acrylic, this can lead to murky edges. For this reason, we reduce the compressed air to a minimum and use only a minimal amount of rinsing air, which protects the optical lens from contamination.
When cutting thick acrylic, flammable cutting emissions are more likely to occur. To reduce the gas concentration and to better distribute excess laser energy, we recommend the use of spacers between the table surface and the material. Our unique extraction concept then takes over from here, with uniform extraction power everywhere on the table.
With our eurolaser system, you can adjust the cutting focus individually. In order to obtain the straightest possible cutting edge, even with thick acrylic, it is recommended to place the focus point lower, approximately in the center of the material. If you set the focus point on the surface instead, you risk that the beam underneath is no longer focused and the squareness of the cutting edge suffers as a result.
Because a clean cut edge requires a rather slow cutting speed, the acrylic is exposed to a lot of heat over a long period of time. To avoid discoloration or even burns, a protective film should be used. The transport or protective film from the manufacturer is usually sufficient for this purpose. Alternatively, an additional protective film can be applied.