Finding the Right Power Setting

Working in the laser industry, I often field questions about proper power and speed settings. These questions are often difficult to answer as there are numerous variables that must be considered when seeking the proper settings. The type of substrate, thickness of the substrate, and laser wattage all factor into what settings will properly mark the material. For instance, aluminum conducts energy much better than steel, a thicker substrate will remove energy much faster than a thinner one, and a higher power laser can deliver more energy than a lower power laser. So what is the magic equation that crunches these variables into a perfect power and speed setting?

Well, in short, there is no equation that can calculate the perfect setting. But, there is a method which will allow you to quickly and efficiently determine a proper power and speed setting for any type of substrate you choose to mark. The key is to make a power/speed grid.

First, obtain a piece of your substrate, spray it with your marking material and focus it in your laser. (A scrap piece of the substrate is best, if possible, because you will ruin it making the grid).

Next, design a varying power/speed grid. For example, on stainless steel:

Steel 100P/50S
Steel 100P/40S
Steel 100P/30S
Steel 100P/20S
Steel 100P/10S

In this grid, P stands for % Power and S stands for % Speed. Adjust your lasers settings to match your selected colors and mark the substrate.

After you have marked the object, you should observe a variation of marks. They should range from barely visible to a slight destruction of the substrate. Pick a pair of settings that give a durable mark of the appropriate color that also maximizes your lasing speed.

Using this method first, when marking a substrate for the first time, can save you time and money. You are sure to only waste one piece of your substrate while quickly finding the optimum settings for the marking you need to do.

If you are using a lower power laser, i.e. 25 or 30 watts, and having trouble marking certain substrates, here is another tip. You can increase your Dots Per Inch (DPI) and deliver more energy to the surface of the substrate. Most lasers have a default setting of 500 DPI, but can be increased to 1000 DPI.

-LaserStud