Laser Engraving is a Subtractive Manufacturing method, that uses a laser beam to change the surface of an object.
This process is used to create images and text (Like Logo’s and other art work) on the material, that may be seen at eye level. The laser creates high heat that will vaporize the material, thus creating cavities that will form the final image. It is using the laser for marking the surface of an item.
How does Laser engraving work?
With software that turns the image or text into machine code, and this code is then send to the laser machine. The method is quick, as the material is removed with each pulse of the laser. The depth of the marks is controlled by the power of the laser beam and the speed of how fast the laser is moving and the amount of times the laser beam is passing on the material.
There are different types of laser engraving machines:
First ones are engraving machines where the work-piece is not moving, only the laser moves or the work piece moves and the laser is stationary. Other machines use rotary attachments to engrave on cylindrical work-pieces. The other possibilities are laser engraving machines where the laser and the work-piece are both immobile but galvo mirrors are moving the laser beam on the surface to engrave.
What is it possible to do with Laser Engraving?
It can be used on almost any kind of metal, plastic, wood, leather or glass surface. You can get a lot of different engraved materials. Furthermore, it is more effective than traditional rotary engraving tools for small objects, such as jewellery and very fine detail is possible with a laser. There are also smaller chances to damage or deform the material. It can be used for many different applications, such as medical devices, fine art and so on.
It can be used for industrial applications (barcodes and or text on panels), but it is also possible to get a DIY laser engraver machine, for example with a CO2 laser system. You just have to connect your CO2 laser engraving machine to the USB port of your computer and it will work like a printer.
Different Laser types can be used including Diode lasers, CO2 lasers, Fibre lasers. And each laser is has its limitations.
Difference between Laser Etching and Laser Engraving
Laser Etching is a subset of Laser Engraving. In this particular case, the heat from the beam is not used to vaporize the material, but to change its color. It is mostly used on metals, and will expand the material. It thus modifies its characteristics, such as its reflectivity, and will create a contrast with its surroundings.
Compared to other processes using lasers, such as Laser Cutting or Laser Etching, Laser Engraving keeps the initial shape of the material, and is the most common option to create personalized or customized objects. Logos, serial numbers, or pictures are typically the kind of creations that can be done thanks to Laser Engraving.
Laser Marking is common and quite popular in the medical device industry. One of the major difference with Laser Engraving and Laser Etching is that here, the oxidation during the marking process make the material turn black. This laser marker technique is also good for logos or bar codes.
This Laser Engraving system does not work with any 3D file format, such as .stl file formats.
The model will be converted into dots, and the distance between two of these dots will determine the depth of the engraving. Then the 2D model will be sent to an engraver machine
The machines used for Laser Engraving or Laser Marking are the same as the ones used for Laser Cutting.