Acrylic sheets are produced using one of two techniques - extrusion and casting. Each approach solves certain problems and imparts certain properties to the material. When machining different types of acrylic (cast or extruded) it is necessary to consider their properties. This also applies to laser cutting of this material.
Which plexiglass to choose for laser cutting?
According to experts, the best option for cutting on a laser engraver is cast acrylic. Sheets of this material are laser machined well because it has no residual stress. This makes it possible to obtain high-quality products. However, the thickness consumption of the sheets is quite high and it is important to take this into account when manufacturing prefabricated product parts. Cast acrylic is more expensive than extruded acrylic.
The thickness of extruded acrylic consumes less. However, a few days after machining or cutting on a laser machine, the residual stress present in it can cause cracks. This makes the material less suitable for laser processing.
Features of Laser Cutting Acrylic
When cut with a laser, acrylic releases substances that are harmful to human health. To prevent inhalation of such components, it is important to close the machine cover when processing acrylic. An exhaust hood is also required to remove the flammable vapors that are produced.
How to adjust cutting speed and power?
The speed and power of the machine when cutting acrylic is set according to the power of the laser tube installed in the device. In most cases, use the same parameters as cutting plywood.
It's important to choose parameters like this so that you can make a cut in one go. The more passes the laser passes over the plexiglass, the lower the quality of the finished product.
This is due to the settling of the plexiglass vapor on the cutting edge during the second and subsequent passes. Because of this, it becomes rough and bubbly. This is especially noticeable on sheets with a thickness of 5-10 mm.
It is recommended to use the sample project to set power and speed. This will help avoid problems when you start cutting the actual product. If sample testing shows that the material cannot be cut on the first pass, the laser power needs to be increased or the speed of the laser head reduced.
What are the important things to consider when laser processing acrylic?
The first rule that contributes to high quality results is accuracy. The simple processing of plexiglass has a disadvantage - it is easily damaged by the laser.
To prevent this from happening, pre-fasten the sheets securely to the table. It has to be completely still, because even a small change is guaranteed to be wasted.