Adjusting Metal Engraving Parameters: A Guide to Common Materials

The guide provides tips on how to set up the laser for various common metals, including stainless steel, aluminum and copper. It also provides reference values for core parameters such as laser power, speed and frequency, and shares solutions to problems such as uneven coloration and insufficient depth. This is all designed to help newcomers quickly get to grips with metal engraving.

Three key points to keep in mind when adjusting parameters for metal engraving.

When people first encounter a laser engraver, they often get intimidated by all the parameters.In fact, adjusting these parameters is a lot like controlling the heat when cooking. Mastering these core elements can keep you from "flipping out.

The type of material dictates the basic configuration.

Stainless steel requires high power (for example, 70-80 % of the power of an 80W fiber laser) while aluminum is easily reflective, so if the power is too high it can burn the metal.For metals with high thermal conductivity, such as copper, increasing the frequency (to 20 kHz, for example) can produce a sharper mark.

The balance between speed and power.

If the speed is too fast, the engraving may not be deep enough; if it's too slow, the material may be burned.For example, to engrave a business card made of 304 stainless steel, a speed of 800 mm per second and 65 % power are sufficient to ensure clarity without damaging the surface.If the ink is oxidizing and turning black, try raising the printing speed to 1000mm / s.

Focus on the focus, or your pictures will be ten times worse.

Beginners often complain that their engravings come out blurry, and 80 % of the time it's because they haven't adjusted the focal length properly.Here's a simple method of finding the focal plane: Place a sheet of A4 paper on the material you want to cut, and adjust the focal length until the laser is burning through the paper without igniting it.

Table of parameters for five common metal materials.

Below are some of the parameters I measured in the workshop that can be achieved with an ordinary 20W fiber laser (units: mm / s): 1.

Engraving on stainless steel.

Power: 75 %, Speed: 700, Frequency: 15 kHz, Wire spacing: 0.08.

Note: For coated surfaces, use low power (30 %) to avoid splashing of coating.

Aluminum alloy phone cases.

Power: 55 % / Speed: 1200 / Frequency: 18kHz / Marking Mode: Line-by-line scanning.

A trick of the trade: Spraying a matte finish on the surface before etching can solve the problem of insufficient contrast caused by reflection.

A copper seal with deeply carved characters.

Power: 85 % Speed: 400 Frequency: 25 kHz Number of passes: 2.

Before engraving, be sure to use alcohol to remove the surface oxide layer, or the surface will appear iridescent.

Don't panic if you run into these problems.

The edges of the characters are rough.

90 % of the time, it's because the lens is dirty. Just wipe the lens with anhydrous alcohol.It is also possible that the air assist is off. Be sure to turn on compressed air (0.2 MPa is sufficient) when cutting copper or aluminum.

The depth of the grooves is uneven, like the pattern of waves.

Check that the platform is even, especially when carving large patterns.An old-timer taught me a little trick: put a piece of paper on each corner, and adjust the tension so that the resistance is the same on all four sides.

The material changes shape after being stamped.

Thin sheets (< 1 mm) should be operated at no more than 40 % power, or pulse mode should be used.Last year, a customer was carving a 0.5 millimeter-thick copper sheet. After switching to 10 % power and 300 millimeters per second, the results were immediate.

Finally, it should be remembered that specifications are just guidelines, and there are differences in performance between different manufacturers.The best way is to first cut a piece of scrap material and start in the middle of the range, adjusting in small increments and recording the results of each change.