Acrylic is a form of plastic that serves as a shatter-proof alternative to glass, and makers use it for a wide variety of applications. Also known as Plexiglass, acrylic is ideal for bullet-proof windows, signs, walls, aquariums, and protective shields, to name just a few common uses of the material. Despite its high impact resistance, you can easily cut or engrave an acrylic sheet with a laser cutter.
photo credit: Pauls Workshop / YouTube
The following are a few tips for working with this material.
1. Use The Right Size Laser Cutter
Acrylic sheets come in sizes ranging from approximately 2 to 6 feet in width and 6 to 8 feet in length. As boss lasers reviews indicate, it’s best to work with a laser cutter that’s big enough to accommodate a large sheet rather than having to cut the acrylic into smaller pieces or pay extra for custom sizing. In terms of power, you’ll need 10 watts of laser power per millimeter of thickness. Acrylic sheets can be anywhere from just 1.5 mm thick to more than 100 mm (4 inches) thick.
2. Choose Extruded Acrylic For A Flame-Polished Edge
There are two forms of acrylic, extruded and cell cast. Extruded acrylic is a less expensive product, and it works well for most types of manufacturing. The process of extrusion yields a highly uniform sheet of acrylic that is suitable for a range of fabrication methods. Because the material has a very high tolerance for heat, a laser cut will leave a smooth, flame-polished edge. If you’re engraving, be aware that the etched lines will be clear rather than frosted.
3. Choose Cast Acrylic For A Frosted-Glass Look
Cast acrylic is made by pouring a liquid into a mold or between glass plates, and it results in a high-quality, somewhat more expensive material. Of the two types of acrylic, cast acrylic is the better choice for engraving because the etched surface mimics the look of frosted glass. However, the thickness of cast acrylic is not quite as consistent as that of extruded acrylic.
4. Raise The Sheet Off The Cutting Table
When the laser beam enters an acrylic sheet, the light bounces off the metal surface of the cutting table, which does not absorb laser light. The reflection can actually burn the bottom surface of the laser sheet, creating pits or discoloration. By lifting the sheet above the table with pins or shims placed in areas where the laser doesn’t cut, you can make room for air to flow and for heat to dissipate.
5. Use An Exhaust System
When you use a laser to cut acrylic, the process will create fumes that, while not toxic, can still be damaging to the lungs. Besides that, the odor can be unpleasant. Thus, using an exhaust system to keep the air clear is key to laser cutting safety. An exhaust system employs a fan to draw the fumes away from the laser and then direct them into a duct system that is vented to the outdoors.
There are really two main factors that determine success when working with acrylic: the quality of the acrylic sheet and the laser cutter settings. Choose acrylic sheets that are glossy and free of pockmarks or any other obvious irregularities. Also, make sure to do a test cut to check the laser cutter’s settings. Try experimenting with small variations in strength and power until you get the results you want.