What do the laser parameters mean?
Optimal laser parameters for laser engraving and laser cutting for CO2 laser applications
What do these parameters such as power, speed, ppi, Hz, pass, Air Assist, z-offset actually mean? Here is a brief explanation.
Power and speed parameters
The power and speed laser parameters are the most important settings in the material database. They can be set as a percentage between 0 and 100%.
The Power laser parameter describes the output power of the laser. 100% is maximum power. For dark wood engravings or stamp engravings, you generally need high power, whereas low values are used for materials such as paper.
The Speed laser parameter describes the movement of the laser head. Fast speeds lead to short exposure times, slow speeds lead to long exposure times. For example, large-scale engravings of TroLase materials are engraved at high speeds between 80 and 100%, but for photo engravings with lots of detail on wood, the speed should not exceed 10%. This setting also affects the quality of the laser cut.
Note that cutting and engraving speeds are not comparable. Basically, cutting is slower than engraving. A "high" cutting speed is 10%.
PPI and Hz parameters
The PPI parameter (=pulses per inch) determines how many laser pulses per inch are used for the engraving. To achieve a good result, this should be the same or a multiple of the dpi selected in the print setting. In Ruby® the PPI settings are adapted to the DPI settings automatically. If you set this parameter to "Auto," JobControl automatically determines the optimal resolution of the laser pulses.
During the cutting process, the Frequency parameter is decisive and is given in Hz (=Hertz). It specifies the number of laser pulses per second. For a CO2 laser, the value can be set within a range of 1,000 to 60,000 Hz. For example, if you want to achieve a smooth edge when cutting acrylic, you need higher temperatures and thus this value is set to at least 5,000 to 20,000 Hz. On the other hand, when cutting wood a low frequency of 1000 Hz is necessary in order to achieve, for example, the brightest possible cutting edge.
Air Assist parameter
During laser engraving and laser cutting, the supply of compressed air can significantly influence and improve results. Furthermore, Air Assist protects the lens from damage, as it stops dust from adhering to it in the first place. However, there are applications in which the Air Assist is deliberately switched off. When engraving TroLase engraving materials, for example, a more attractive engraving result is achieved without Air Assist. In this case, the lens must be checked for contamination more frequently than with Air Assist.
Helpful hints for determining laser parameters
How can I quickly and easily determine the optimal laser parameters for my material? We have summarized some tips & tricks for you.