How to run a fiber laser test grid in EZCAD2

A diode laser has two main variables: speed and power. A fiber laser adds frequency (how many pulses per second the Q-switch fires) and, on MOPA machines, pulse width (how long each individual pulse lasts). These four parameters interact. The combination determines whether you get a deep black mark, a surface etch, or a reflective polished finish. Settings from a forum post will not work unless the machine, focal length, and optical power match yours exactly.

A test grid maps this space quickly. Burn a full matrix of speed and power combinations in one pass. Read the results and pick the best cell. What used to take an afternoon takes fifteen minutes.

Speed and power: the two axes

Speed and power are the primary test axes for any laser type. High power at low speed drives more energy into the material and produces a deeper, darker mark. High speed at low power produces a lighter surface mark. For most engraving work on anodized aluminum or coated tumblers, find the combination that gives a clean, consistent black without burning through the coating.

Starting range for anodized aluminum: speed 500 to 2000 mm/s, power 20 to 70%. For stainless steel with cermark or marking paste: speed 200 to 800 mm/s, power 30 to 80%. For bare metal color marking on a MOPA machine, use a narrower speed range and test pulse width as a separate variable.

Frequency and pulse width: fix one, test the other

For a standard Q-switched fiber laser (not MOPA), frequency is the key secondary variable. It controls how many times per second the laser pulses. Common starting points are 20 to 80 kHz. Lower frequency (20 to 30 kHz) puts more energy per pulse into the material. This works well for deep marking. Higher frequency (60 to 100 kHz) spreads energy across more pulses. This is better for fine surface engraving on sensitive coatings. Pick a frequency that matches your goal, hold it constant, and use speed and power as your test axes.

On a MOPA machine, pulse width is an additional variable. Short pulses (2 to 10 ns) produce a high-contrast mark on anodized aluminum without damaging the base metal. Longer pulses (100 to 500 ns) go deeper and work better for stainless steel and bare metals. Color marking on stainless requires very short pulses (4 to 10 ns). Those settings are highly sensitive to speed and power. Run a test grid before any production job. For a MOPA test, choose a target pulse width, hold it constant, and test speed and power across the grid.

How to use the EZCAD2 test grid generator

The generator produces two files: a DXF file for the geometry and a CSV file with the laser parameters for each cell.

Step 1: Open the test grid generator. Set your speed and power ranges. For a first test on a new material, use a wide range such as 300 to 1500 mm/s speed and 20 to 80% power. Set 5 steps on each axis for a 5 by 5 grid of 25 cells. Set your cell size to 5 mm for a compact test or 10 mm if space allows. Enter your baseline frequency and pulse width in the fiber/galvo section.

Step 2: Download the DXF and CSV. The DXF contains one rectangle per cell, each on its own named layer. Layer names encode the settings. For example, S500P40 means 500 mm/s speed and 40% power. The CSV lists those layer names with every parameter: speed, power, frequency, pulse width, passes, and hatch spacing.

Step 3: Import the DXF into EZCAD2. The layers appear in EZCAD's layer list. Open the CSV alongside EZCAD. Configure each layer by finding its name and entering the parameters from the CSV row. A 25-cell grid takes a few minutes to configure. Save the file when done. You can reuse it for the same material on the same machine.

Step 4: Clamp your test piece. Focus correctly. Run the job. Keep the CSV open so you can identify each cell.

Reading the results

On anodized aluminum, look for the darkest consistent black with clean edges. White spots indicate the coating burned away unevenly. Undercutting means too much heat spread. The ideal mark has sharp edges and even color.

On coated tumblers (powder coat or epoxy), look for complete removal of the coating with a clean edge. Hazing of the base metal means too much energy. Reduce power or increase speed. Incomplete removal means not enough energy. Adjust in the opposite direction.

On bare stainless for color marking (MOPA only), results depend on pulse width more than speed and power. If you see no colors appearing, your pulse width is probably too long. Run a second test at a shorter pulse width. The typical range for stainless color marking is 4 to 8 ns.

Note the layer name of the best cell. The CSV gives you speed, power, frequency, and pulse width. That is your repeatable parameter set for the material.

Starting points by material

These are starting ranges, not confirmed settings. Your machine's optical power, focal length, and spot size all affect the result. Always test on scrap before committing to production material.