LONGER Research: Introduction to Color Engraving on Stainless Steel with Nano Pro 12W

Color laser engraving on stainless steel allows users to create vibrant patterns by adjusting laser settings instead of using paints or coatings. With the LONGER Nano Pro 12W and LightBurn, different colors can be achieved by changing parameters such as laser power, speed, and the number of passes.

This guide introduces the basic principles of stainless steel color engraving, explains how to generate a color parameter matrix in LightBurn, and shows how to apply those parameters to layered designs.

Principle of Laser Color Engraving

For color laser engraving on stainless steel, the techniques are mainly divided into two categories: the first involves the laser beam instantaneously heating the metal surface, triggering physical or chemical reactions that alter the surface color. The second involves the formation of colored oxides on the metal surface or the generation of a transparent, colorless oxide layer, which displays various colors through thin-film interference effects.

By precisely adjusting key parameters such as laser power, engraving speed, spacing, and the number of passes, users can effectively control the reaction depth on the metal surface, achieving a variety of color effects to meet different processing needs.

Testing Color Engraving Parameters

The following parameter testing process is based on the LONGER Nano Pro 12W using stainless steel.

Generate a Material Test in LightBurn

LightBurn includes a Material Test feature that automatically creates a parameter matrix for testing different engraving settings.

Set the required ranges for: Power, Speed, Interval, Passes. These parameter combinations determine the colors produced during engraving.

Prepare the Machine

Before generating the test file:

1. Open LightBurn.
2. Import the Nano Pro configuration file.
3. Select the correct COM port.
4. Connect to the Nano Pro.

When the console displays "Nano Pro connected successfully," continue with the material test.

Configure the Material Test

Open Laser Tools and select Material Test. For the Nano Pro, the recommended test range is:

• Power: 50%–100%
• Speed: 1000–3000 mm/min
• Matrix Size: 11 × 11

After confirming the settings, click Start to begin the engraving test.

Read the Test Results

After the test finishes, LightBurn generates a color matrix. The matrix makes it easy to identify the parameter combination for each color.

• The horizontal axis represents laser power.
• The vertical axis represents engraving speed.

Choose the desired color and record the corresponding parameter values for future projects.

Creating a Color Engraving

After determining the required parameters, import your design into LightBurn.

1. Open File > Import and load the layered vector image.
2. Connect the Nano Pro.

Select the first section of the design and assign it to Layer 1. This layer will use the engraving parameters for the first color.

Select the first section of the design and assign it to Layer 1. This layer will use the engraving parameters for the first color.

Once all layers have been created, apply the corresponding laser parameters from your color test matrix to each layer. Different parameter combinations produce different colors on the stainless steel surface.

After confirming all settings, start the engraving job. In this example, the butterfly is engraved with the selected parameters to create a blue color effect.

Precautions for Color Engraving on Stainless Steel

Keep Laser Power Above 50%

For stainless steel color engraving, laser power should remain above 50%. Lower power levels may produce very light colors, with yellow being the most common result. Precise power adjustment is important for achieving consistent color variation.

Choose the Right Stainless Steel

For better engraving results:

• Use stainless steel that is at least 2 mm thick.
• Matte or brushed stainless steel is recommended.

Very thin sheets may deform because of heat buildup. Industrial-grade or mirror-finished stainless steel may not produce the expected engraving results.

Maintain Accurate Focus

Correct focus is essential for consistent color engraving. Before each job:

• Confirm the laser is properly focused.
• Make sure the Nano Pro is placed on a level surface.

Incorrect focus height can affect color consistency and engraving accuracy.

Conclusion

Color engraving on stainless steel requires careful parameter testing and consistent machine setup. By using the Material Test feature in LightBurn, recording the best parameter combinations, and maintaining proper focus, Nano Pro users can achieve stable and repeatable color engraving results on stainless steel.