Laser Engraver Blogs

UV Ink Types Explained: A Practical Guide for UV Printer Users
UV Ink Types Explained: A Practical Guide for UV Printer Users

UV printing technology has become widely adopted across industries such as product customization, advertising signage, packaging, industrial labeling, and decorative printing. Modern equipment including the desktop UV printer, flatbed UV printer, and UV DTF printer, allows users to print directly onto hundreds of materials, from rigid substrates like glass and aluminum to flexible surfaces such as films, leather, and TPU transfer sheets.

However, stable print quality and long-term durability do not depend solely on the printer itself. In real-world production environments, ink formulation plays an equally critical role. Different materials require UV inks with specific mechanical properties such as hardness, elasticity, adhesion, and curing speed.

Over the years working in UV printing system development and material testing, I’ve seen many cases where print issues: peeling, cracking, poor adhesion, or color instability, were not caused by the printer hardware but by using the wrong ink type for the substrate.

This guide explains the most common UV ink types used in modern UV printing, including rigid inks, flexible inks, hybrid inks, white inks, varnish, and specialized inks for decorative and industrial applications. It also discusses how modern equipment such as the Longer ePrint dual-printhead UV printer supports multiple ink types and advanced printing techniques for both professional users and small businesses.

Why Choosing the Right UV Ink Matters

In UV printing, ink is cured through photopolymerization. When exposed to ultraviolet light, liquid ink rapidly converts into a solid polymer film. The chemical composition of the ink determines how that film behaves once cured. In practice, that cured ink layer must match the mechanical behavior of the material underneath it. 

For example, printing rigid ink on flexible PVC film often results in cracking when the material bends. Using overly soft ink on glass may lead to scratching or poor durability.

During an early material compatibility test in our lab, we printed a flexible vinyl banner using a rigid UV ink formulation. The print initially looked perfect, but when the banner was rolled for shipping, fine cracks appeared along the folds. The issue was solved simply by switching to a flexible UV ink with higher elongation properties.

Understanding these differences is essential for achieving professional-quality results with a desktop UV printer, flatbed UV printer, or UV DTF printer.

1. Rigid UV Ink

1.1 What Is Rigid UV Ink?

Rigid UV ink is designed for hard, non-flexible substrates commonly used in signage, industrial labeling, and decorative panels. These materials are frequently printed using a flatbed UV printer or a desktop UV printer, where the substrate remains stationary while the printhead moves across the surface.

1.2 Suitable Materials

Rigid UV ink performs well on materials such as:

  • Glass
  • Metal
  • Ceramic
  • Acrylic
  • Hard plastics (ABS, PC, rigid PVC)

These substrates do not deform during use, so the cured ink layer can be optimized for hardness and durability rather than flexibility.

1.3 Key Characteristics

Rigid UV inks are formulated to produce a dense, high-hardness polymer coating after curing. 

Typical properties include:

  • Strong substrate adhesion
  • High surface hardness
  • Good scratch resistance
  • Excellent chemical resistance

For example, when printing industrial metal nameplates, rigid UV ink ensures the graphics remain legible even after exposure to oils, solvents, and outdoor weather conditions.

1.4 Performance Requirements

Typical industry standards include:

  • Pencil hardness ≥ 2H
  • Adhesion passing cross-hatch tape test
  • High abrasion resistance

These characteristics make rigid UV inks ideal for industrial and signage applications.

2. Flexible UV Ink

2.1 What Is Flexible UV Ink?

Flexible UV ink is engineered for soft or stretchable materials that may bend, stretch, or fold during normal use.These inks are commonly used in UV DTF printer workflows, decorative films, and vehicle graphics.

2.2 Suitable Materials

Typical materials include:

  • PVC films
  • Banner materials
  • Wallpaper
  • Leather
  • Textile fabrics
  • TPU transfer films

In fact, TPU films processed with the Longer ePrint system are often used for customized apparel transfers.

2.3 Key Characteristics

Flexible UV inks incorporate elastic polymer binders, allowing the cured ink film to stretch along with the substrate. Unlike rigid ink, flexible ink does not become brittle after curing.

Key properties include:

  • High elasticity
  • Strong adhesion to flexible surfaces
  • Good weather resistance
  • Resistance to UV radiation and moisture

During one field test involving vehicle graphics, flexible UV ink allowed printed vinyl to stretch smoothly over curved body panels without visible cracking.

2.4 Performance Requirements

Typical performance metrics include:

  • Elongation > 200%
  • Strong adhesion on flexible materials
  • High weather resistance
  • Stable UV exposure resistance

These properties make flexible inks essential for UV DTF printing and flexible media production.

3. Neutral (Hybrid) UV Ink

3.1 What Is Hybrid UV Ink?

Neutral UV ink—sometimes called hybrid UV ink—is formulated to provide a balance between rigidity and flexibility. This makes it suitable for substrates that are neither completely rigid nor fully flexible.

3.2 Suitable Materials

Common examples include:

  • Acrylic sheets
  • PS boards
  • PVC foam boards
  • KT boards
  • Composite advertising panels

These materials are widely used in retail displays and indoor signage.

3.3 Key Characteristics

Hybrid UV ink provides balanced mechanical properties:

  • Moderate hardness
  • Moderate elasticity
  • Good color performance
  • Broad substrate compatibility

Because of its versatility, hybrid ink is often used for general-purpose printing on a desktop UV printer, especially in small workshops that print on many material types.

3.4 Performance Requirements

Typical ranges include:

  • Elongation 80–150%
  • Balanced hardness and flexibility
  • Stable adhesion across mixed substrates

This flexibility makes hybrid inks practical for multi-material production environments.

4. White UV Ink

4.1 Why White Ink Is Important in UV Printing

White UV ink is essential for printing on dark or transparent substrates.

Without a white underbase layer, colors printed on dark surfaces often appear dull or transparent.

4.2 Common Applications

White UV ink is widely used for:

  • White underbase printing
  • Layered color printing
  • Embossed texture effects
  • UV DTF transfer film printing

In a UV DTF printer workflow, white ink is usually printed before CMYK layers to create an opaque base.

4.2 Key Characteristics

White UV ink typically contains titanium dioxide (TiO₂) pigment, which provides high opacity and strong light blocking.

Key features include:

  • Excellent covering power
  • Stable flow properties
  • Fast UV curing
  • Strong layer adhesion

Because titanium dioxide particles are heavy, many printers include ink circulation systems to prevent pigment settling.

5. UV Varnish (Clear Ink)

5.1 What Is UV Varnish?

UV varnish—also called clear UV ink—is a transparent coating applied after color printing. It enhances both visual appearance and surface durability.

5.2 Applications

UV varnish is used for:

  • Gloss finishing
  • Protective coating
  • Spot varnish decoration
  • Embossed texture effects

Many modern flatbed UV printers support multi-layer printing, allowing varnish to be applied selectively.

5.3 Key Characteristics

After curing, varnish forms a transparent protective film that provides:

  • Enhanced gloss
  • Increased scratch resistance
  • Improved water resistance
  • Better chemical durability

This technique is commonly used in premium packaging and decorative signage.

6. Specialty UV Inks

In addition to standard inks, several specialized UV inks have been developed for decorative or industrial applications.

6.1 Fluorescent UV Ink

Fluorescent UV ink contains fluorescent pigments that emit light under ultraviolet illumination.

Types: UV-excited fluorescent ink

  • Visible only under UV light
  • Often used as security ink

6.2 Photoluminescent ink

  • Absorbs light and glows in darkness

Applications

  •  Safety signs
  •  Night-time decoration
  •  Entertainment venues
  •  Anti-counterfeiting printing

6.3 Thermoforming (Vacuum Forming) UV Ink

Thermoforming UV ink is specifically designed for vacuum forming plastics such as PVC and PET sheets.

Key Properties

  • High temperature resistance
  • Strong adhesion
  • Excellent flexibility

During thermoforming, materials may be heated to 60–120°C and stretched into molds. Specialized UV ink ensures that the printed graphics do not crack or peel during deformation.

6.4 Embossed Texture UV Ink

Embossed UV ink is formulated with thixotropic resins, allowing the ink to build thick layers during printing.

Characteristics

  • Creates 3D textures
  • Height typically 0.5–2 mm
  • Simulates the tactile feel of embroidery

Applications

  • Apparel decoration
  • Bag and luggage branding
  • Textile pattern design

This technique is often used with desktop UV printers that support multi-layer printing.

6.5 Foil Stamping UV Varnish

Foil stamping varnish is a transparent adhesive UV layer used to transfer metallic foil.

Working Principle

  1. Print varnish on the desired areas
  2. Apply metallic foil film
  3. Heat press or laminate
  4. Peel off excess foil

Applications

  • Premium packaging
  • Luxury labels
  • Decorative signage

This process provides a faster alternative to traditional hot stamping.

6.6 Leather UV Ink

Leather UV ink is specifically formulated for natural and synthetic leather materials.

Key Properties

  • High flexibility
  • Strong adhesion
  • Resistance to cracking under bending

Applications

  • Leather bags
  • Wallets
  • Furniture upholstery
  • Decorative leather panels

These inks are commonly used in custom leather product printing with desktop UV printers.


FAQ (Frequently Asked Questions About UV Inks)

What type of UV ink should be used for hard materials?

Rigid UV ink is typically recommended for hard substrates such as glass, metal, and acrylic because it provides high hardness and strong adhesion.

Can flexible UV ink be used on rigid materials?

In some cases yes, but flexible inks may have lower surface hardness. For durable industrial applications, rigid inks are usually preferred.

Why is white UV ink necessary?

White ink acts as an opaque base layer when printing on dark or transparent materials. It improves color brightness and image visibility.

What is UV varnish used for?

UV varnish creates a protective transparent layer that improves gloss, durability, and decorative effects such as spot varnish.

Do modern printers support multiple ink types?

Yes. Many modern machines—including advanced systems like the Longer ePrint—are designed to support various UV ink formulations for different materials and applications.

Conclusion

UV printing technology continues to expand across many industries thanks to the versatility of equipment such as the desktop UV printer, flatbed UV printer, and UV DTF printer. However, achieving reliable printing performance depends heavily on selecting the correct UV ink formulation for each substrate and application.

Rigid inks are ideal for hard materials, flexible inks support stretchable substrates, and specialty inks enable advanced decorative effects such as embossing, fluorescence, and foil stamping.

By understanding the properties of different UV ink types—and using versatile printing systems such as the Longer ePrint UV printer—printing professionals and small businesses alike can achieve higher durability, richer visual effects, and greater material compatibility in modern UV printing production. 

Key features include:

  • Dual printheads with 12 ink channels for faster production
  • Open ink system compatible with multiple UV ink formulations
  • Support for standard UV inks, flexible inks, and specialty inks
  • Capability for 3D texture printing up to 60 mm
  • High-resolution output up to 1440 DPI

These capabilities make the printer suitable for home creators,

small businesses, product customization studios and industrial prototype production. Because the system supports over 300 printable materials, users can experiment with different ink types and decorative techniques.

By Laser Engraver Blogs | March 13, 2026
How to Store UV Printer Ink in Winter: A Complete Guide for UV Printer Users
How to Store UV Printer Ink in Winter: A Complete Guide for UV Printer Users

UV printing technology has become increasingly popular among small businesses, makers, and home studios. Compact UV printers now allow users to print directly onto materials such as wood, metal, acrylic, plastic, leather, and fabric.

However, one issue that many new users underestimate is temperature management, especially during the winter months.

UV inks are chemically engineered materials. When exposed to low temperatures, they can become unstable, which may affect printhead performance, droplet consistency, and overall print quality.

After years working in UV printer development and testing—including compact systems designed for creators and small workshops—I’ve seen many printing issues that were ultimately traced back to improper ink storage during cold weather.

In this guide, we will cover:

  • how cold temperatures affect UV ink

  • proper UV ink storage during winter

  • transportation precautions

  • inspection steps after delivery

  • preparation tips before printing

We will also explain how modern printers such as the Longer ePrint UV printer help mitigate these issues with built-in ink temperature control systems.

Why Temperature Matters for UV Ink

UV ink is composed of several sensitive chemical components, including:

  • pigments

  • photoinitiators

  • oligomers

  • monomers

  • stabilizers

These ingredients are formulated to work together within a specific temperature and viscosity range.

When temperatures drop too low, several problems may occur:

  • ink viscosity increases

  • pigment particles may settle

  • droplet formation becomes inconsistent

  • nozzle clogging becomes more likely

In our internal testing labs, we once evaluated ink stored overnight in a warehouse that dropped to around 3°C (37°F). The ink had not frozen, but viscosity increased enough to cause intermittent jetting instability and color inconsistency during printing.

After allowing the ink to return to room temperature for several hours, the printer resumed normal operation. This example highlights how temperature management directly affects printing reliability.

1. UV Ink Storage Guidelines in Winter

1.1 Maintain a Safe Temperature Range

Most UV ink manufacturers recommend storing ink between: 5°C and 25°C (41°F – 77°F). This temperature range keeps the ink chemically stable and ensures proper viscosity.

Recommended storage practices include:

  • store ink indoors

  • keep ink in temperature-controlled environments

  • avoid garages, sheds, or outdoor storage

  • never leave ink in vehicles overnight during winter

When temperatures fall below 0°C (32°F), UV ink may partially freeze or thicken significantly. This can disrupt pigment dispersion and affect long-term print quality.

1.2 Keep Ink Bottles Sealed and Protected from Light

UV inks contain photoinitiators, which react when exposed to ultraviolet light.

For this reason, ink bottles should always be:

  • tightly sealed after use

  • stored in shaded or dark environments

  • protected from prolonged light exposure

 

Air exposure can also cause gradual evaporation or contamination, which may reduce ink stability over time. Professional print shops often store UV ink inside opaque storage cabinets to minimize environmental exposure. 

1.3 Avoid Repeated Freeze–Thaw Cycles

Repeated freezing and thawing is one of the most damaging conditions for UV ink.

Multiple freeze-thaw cycles can cause:

  • pigment separation

  • breakdown of dispersant chemistry

  • permanent viscosity changes

In real printing environments, this often results in:

  • unstable ink jetting

  • inconsistent color output

  • increased risk of nozzle clogging

If ink has frozen, it should be carefully inspected before use.

2. Winter Transportation Tips for UV Ink

Shipping UV ink in cold climates presents additional challenges. Ink packages may pass through unheated trucks or warehouses, exposing them to freezing temperatures for extended periods.

2.1 Use Insulated Packaging

For winter shipping, it is recommended to use:

  • insulated boxes

  • thermal liners

  • foam padding

  • insulated packing materials

Some suppliers also include heat packs inside the package to help maintain internal temperature.

Important note:
Heat packs should not directly touch the ink bottles, as localized heat may degrade the ink.

2.2 Reduce Shipping Time

The longer UV ink remains in transit during winter, the higher the risk of temperature exposure.

To reduce this risk:

  • choose faster shipping services

  • avoid weekend shipping delays

  • minimize warehouse transfer time

In several field cases we studied, ink shipments delayed over winter weekends were more likely to arrive partially frozen.

2.3 Label Packages as Temperature  Sensitive

Shipping labels such as the following can help alert logistics staff:

  • “Temperature Sensitive”

  • “Protect From Freezing”

  • “Handle With Care”

Although not all shipping systems are temperature controlled, these labels improve handling awareness.

3. Inspecting UV Ink After Winter Delivery

When receiving UV ink during winter, users should perform a quick inspection before storage or installation.

3.1 Visual Inspection

Check the ink bottle for the following conditions:

  • signs of freezing or solidification

  • bottle deformation or swelling

  • leakage or damage

  • visible separation or sediment

If the ink appears frozen or damaged, contact the supplier before using it.

3.2 Controlled Thawing

If ink arrives extremely cold or partially frozen, allow it to warm gradually.

A safe method is to place the sealed bottle in warm (not hot) water for a short period.

Avoid high heat, which may alter the chemical composition of the ink.

After thawing, gently shake the bottle and observe:

  • pigment distribution

  • color consistency

  • texture

If separation remains or sediment cannot be mixed back into the ink, it should not be used.

4. Preparing UV Ink Before Printing

Even properly stored ink should be conditioned before use.

4.1 Allow Ink to Reach Room Temperature

Before installing UV ink in a printer, allow it to sit at approximately: 20°C – 28°C (68°F – 82°F) for around 6–12 hours. This ensures the ink returns to its ideal viscosity for stable droplet formation.

4.2 Maintain Stable Printer Temperature

Cold environments can also affect the printer itself. If printing in garages, basements, or workshops during winter, maintaining stable ambient temperatures can reduce:

  • nozzle clogging

  • ink flow issues

  • inconsistent curing

Many modern desktop UV printers now integrate ink heating systems for this purpose.

How the Longer ePrint UV Printer Helps Maintain Stable Ink Performance

Modern compact desktop UV printers increasingly include features designed to improve reliability in non-industrial environments.

The Longer ePrint UV printer incorporates an automatic printhead heating system designed to maintain optimal ink viscosity.

The system operates within the following range:

  • heating begins when temperature drops below 25°C

  • heating stops when temperature reaches 30°C

This automatic regulation helps maintain stable ink flow and improves:

  • droplet consistency

  • printhead reliability

  • long-term print quality

For creators and small businesses working from home studios, workshops, or small production spaces, this feature significantly reduces the risk of cold-weather printing issues.

Combined with its dual-printhead architecture, 1440 DPI resolution, and compatibility with over 300 materials, the Longer ePrint provides a stable and versatile UV printing solution for both personal and commercial applications.

Winter UV Printer Maintenance Checklist

To keep your Desktop UV printer running reliably during winter, follow this simple checklist:

✔ Store UV ink between 5°C and 25°C

✔ Avoid freezing conditions

✔ Use insulated packaging for winter shipping

✔ Inspect ink immediately after delivery

✔ Allow ink to warm to room temperature before printing

✔ Maintain stable printer operating temperatures

✔ Use printers with ink heating systems when possible

Following these steps can significantly reduce printing problems and extend both ink life and printer lifespan.

FAQ About UV Ink Storage in Winter

Can UV ink freeze?

Yes. If exposed to temperatures below 0°C (32°F), UV ink may partially or fully freeze. Freezing can damage the internal pigment dispersion and affect printing performance.

Can frozen UV ink still be used?

Sometimes. If the ink is thawed slowly and returns to a normal appearance without separation, it may still function properly. However, severely frozen ink should be replaced.

What temperature should UV ink be before printing?

UV ink should ideally be between 20°C and 28°C (68°F – 82°F) before printing to ensure proper viscosity and stable droplet formation.

Do modern Desktop UV printers help manage ink temperature?

Yes. Some modern compact Desktop UV printers include ink heating systems to stabilize viscosity. For example, the Longer ePrint UV printer automatically warms ink when temperatures fall below 25°C, helping maintain consistent print performance.

Final Thoughts

Winter conditions can introduce challenges for desktop UV printing, particularly when it comes to ink storage and transportation.

Fortunately, most problems can be avoided through proper handling practices and by using printers designed with temperature stability in mind.

By storing ink correctly, inspecting shipments carefully, and maintaining proper operating temperatures, users can ensure consistent printing performance throughout the colder months.

For many creators, makers, and small business owners entering the UV printing space, adopting these simple habits can make the difference between frustrating printing issues and smooth, reliable production.

By Laser Engraver Blogs | March 13, 2026
Nano Duo Stainless Steel Color Engraving Guide
Nano Duo Stainless Steel Color Engraving Guide

Nano Duo allows precise color engraving on stainless steel by forming oxide layers or thin-film interference colors. Using the LaserBurn software, users can easily test and determine optimal engraving parameters to achieve the desired colors on stainless steel. This guide covers material preparation, parameter testing, layer-based color engraving, and practical use cases.

Stainless Steel Color Engraving Principle

Color formation by laser:

When stainless steel is heated by a laser, colored oxides or a transparent oxide film form on its surface. Thin-film interference causes various colors to appear. Oxidation products of metallic elements also contribute to the coloration.

Oxide color

Oxidation products of stainless steel elements naturally display color.

Oxide thin film interference

Under suitable laser energy, a colorless transparent oxide film forms on the surface, producing optical interference and resulting in various colors.

Material Preparation

Software: LaserBurn

Machine: Nano Duo

Material: Stainless Steel

File: Color Engraving File

Note: Material testing is required before engraving to obtain optimal parameters.

Use Cases

Medical devices, decorative items, automotive marking, architectural decoration, etc.

How do I use Nano Duo to test parameters for different colors on stainless steel?

This color engraving parameter guide is based on the Longer Nano Duo model machine, using stainless steel as the metal material. Utilizing the "Material Test" function in the LaserBurn software, the preparation of engraving parameter test files is greatly simplified. Users can input relevant parameter ranges in the "Material Test Generator" to automatically generate test files. Key parameters include power, speed, interval, and number of engraving passes; these combinations directly affect the engraved color. By setting appropriate parameter ranges according to the specific dimensions of the material, users can generate corresponding engraving test files.

Operating procedures:

Step 1

Open LaserBurn and ensure the device is successfully connected to the software (click "Device" in the upper right corner—"Connect"—select "Nano Duo"—click "Confirm").

(Connection page)

(Operation page in connection)

(Page after successful connection)

Step 2

Draw a 10×10 mm square on the canvas and set it to Fill mode. Click "Array" in the toolbar and select "Material Test." A parameter matrix interface will appear.

Recommended parameter range for Nano Duo:

Power: 50% to 100%

Speed: 1000 mm/min to 3000 mm/min

Matrix layout: 10×10

Ensure all parameters are correct, then click Confirm to create the test file. Finally, click Device → Engraving → Laser Focus (two points coincide) → Frame → Start Engraving, and wait for completion.

After the engraving test is completed, the system will generate a color matrix (as shown in the figure). Users can select the desired color from the matrix and find the corresponding laser power and speed. The horizontal axis of the matrix represents the power parameter, and the vertical axis represents the speed parameter. Users can easily determine the required engraving settings by matching the coordinate positions.

How to create colorful sculptures

As shown in the image, we import the image and perform a layer split on the vector image:

Step 1

First, select the part of the vector image to be sculpted.

Step 2

Click the bottom right corner to set layer 1.

Step 3

As shown in the image, we set the leaf part as a layer.

Step 4

Next, set the second layer.

Step 5

As shown in the image, select the center part of the letter.

Step 6

Then, set the 3rd layer.

Final Result

Finally, we obtain the complete layered vector of the material, as shown in the figure. Then we match the corresponding parameters for the desired colors. After completion, the engraving will produce the ideal color image.

We eventually received a colored badge.

Conclusion

By properly testing and setting parameters, the Nano Duo can achieve high-quality color engraving on stainless steel. Users can adjust power, speed, interval, and passes to achieve the desired color effects. This method is suitable for decorative items, metal signage, and other precision applications, providing a reliable solution for stainless steel color engraving.

By Laser Engraver Blogs | March 11, 2026
How to Use Nano Duo Visual Correction
How to Use Nano Duo Visual Correction

Introduction

The NanoDuo Visual Correction function is designed to improve engraving accuracy by using the machine’s built-in camera to align the engraving position with the working area. By calibrating the camera and the laser workspace, the system can automatically adjust the engraving placement based on the captured image.

Before using the NanoDuo's several vision-related features for the first time, you'll need to perform visual alignment. This involves sculpting a target marker pattern and then marking it in the photo sent by the camera. Before starting, ensure that no other apps are using the NanoDuo's camera.

Precautions

Place the engraving paper in the engraving work area (use the provided white engraving paper).

When using the vision correction function, ensure no other cameras are connected and that the machine's camera is not in use.

Do not move the machine or the engraving paper during the vision correction process. Ensure the correction process is completed in one go.

Do not reuse the engraved pattern for correction; a new marking pattern must be engraved.

Engraved Marking Graphics

You will use your laser to engrave a target pattern on a piece of material and mark the center of the target.

1. first step

After connecting the nanoDuo, click the camera icon that appears in the menu bar to enter the vision correction function page.

Before entering the visual correction function page, please scale the canvas and move it to the side so that the entire canvas can be seen properly after the visual function page is opened.

2. Step 2

Enter the appropriate speed and power settings to achieve moderate engraving without burning through, and increase or decrease the scaling value until the canvas can accommodate the marked pattern.

3. Step 3

Click the Border Preview button to display the marker pattern on the canvas, ensuring it does not exceed the canvas size.

Note: Each time you modify the speed, power, and scaling values, you need to click the border preview button again to update the marker pattern on the canvas.

 4. Step 4

Click Start. If it's not clear enough, you can adjust the settings and run it again. When the pattern is clear and easy to see, click Complete,You may need to wait a few seconds on this screen for the camera to successfully capture your image.

 

By Laser Engraver Blogs | March 10, 2026
How to Fix CH340 Driver Installation Failure on Longer Laser Engravers
How to Fix CH340 Driver Installation Failure on Longer Laser Engravers

Introduction

This document summarizes the common causes and solutions for CH340 driver installation issues on both Windows and macOS systems. It explains how to resolve problems related to system compatibility, driver conflicts, permission restrictions, USB cable issues, and security settings. It also provides methods to verify whether the driver is installed correctly and suggests alternative solutions if installation continues to fail.

By following the troubleshooting steps in this guide, users can quickly diagnose driver installation problems and restore normal communication between their device and computer.

Windows System

Common Causes and Solutions

1. System Compatibility Issues

Windows 10 and Windows 11 usually include a built-in driver for the CH340 chip. However, automatic installation may occasionally fail.

Solution

Download and install the latest driver manually from the official website:
https://www.wch.cn

Install the latest version of the driver package CH341SER.EXE.

2. Old Driver Conflicts

If an older version of the CH340 driver was previously installed, it may conflict with the new installation.

Solution

  1. Open Device Manager.

  2. Click View → Show hidden devices.

  3. Expand Ports (COM & LPT).

  4. Right-click any CH340/CH341 related devices and uninstall them.

  5. Select Delete the driver software for this device if prompted.

  6. Reinstall the latest driver.

3. Driver Signature Issues

Some systems, especially Windows 7 and certain Windows 10 configurations, may block unsigned drivers.

Solution

  1. Restart your computer.

  2. Enter Advanced Startup Options.

  3. Select Disable driver signature enforcement.

  4. Run the driver installer again.

4. Insufficient Permissions

Installing drivers requires administrator privileges.

Solution

Right-click the installer and select Run as administrator.

5. USB Cable or Port Problems

Some USB cables only support charging and do not transfer data. If such a cable is used, the device will not be recognized even if the driver is installed.

Solution

  • Use a USB cable that supports data transfer.

  • Connect the cable directly to the computer’s USB port (preferably USB 2.0).

How to Confirm the Driver Installation

  1. Connect the Longer laser engraver to your computer.

  2. Open Device Manager.

Under Ports (COM & LPT) you should see something similar to:

USB-SERIAL CH340 (COM3)

If this appears, the driver has been installed successfully.

If a yellow warning icon appears, the driver installation may have failed or there may be a driver conflict.

Alternative Solutions

If the driver still cannot be installed:

  • Try using another computer to rule out system-related issues.

  • Replace the adapter module with FT232 or CP2102, which often offer better compatibility.

macOS System

1. Check Whether a Driver Is Needed

Starting from macOS 10.13, the CH340 chip may sometimes be recognized automatically without installing a driver.

  1. Connect your Longer laser engraver.

  2. Open Terminal and enter:

ls /dev/tty.*

If you see a device such as:

/dev/tty.wchusbserial1410

The device has been detected successfully and no driver installation is required.

2. Install the Driver (If the Device Is Not Recognized)

Download the Driver

Official driver
https://www.wch.cn/downloads/CH341SER_MAC_ZIP.html

Open-source driver (recommended)
https://github.com/adrianmihalko/ch340g-ch34g-ch34x-mac-os-x-driver

The open-source version often provides better compatibility with newer macOS systems.

Allow System Extensions

During installation, macOS may display a message such as “System Extension Blocked.”

To allow the driver:

  1. Open System Settings / System Preferences.

  2. Go to Security & Privacy.

  3. Under the General tab, click Allow for WCH Electronics Co., Ltd.

Restart Your Computer

After installation, restart your Mac so the driver can be loaded correctly.

Troubleshooting Common Issues

Driver Installed but No Port Appears

Open Terminal and run:

ls /dev/tty.*

Disconnect and reconnect the USB cable to check whether a new device appears.

Apple Silicon Macs (M1 / M2 / M3)

Many official drivers were originally designed for Intel-based Macs, which may cause compatibility issues on Apple Silicon devices.

For better stability, we recommend using the open-source driver from GitHub mentioned above.

Permission Restrictions on New macOS Versions

Recent macOS versions such as Big Sur, Monterey, and Ventura enforce stricter security policies for third-party drivers.

If the Allow option does not appear in Security & Privacy, you may need to:

  1. Restart your Mac in Recovery Mode.

  2. Temporarily disable System Integrity Protection (SIP).

  3. Install the driver again.

Alternative Options

If you still cannot install the CH340 driver, you may consider these alternatives:

  • Use an FTDI USB-to-serial module, which macOS supports natively without additional drivers.

  • Use a Wi-Fi connection if your GRBL controller board supports wireless communication.

By Laser Engraver Blogs | March 5, 2026
Nano Pro Stainless Steel Color Engraving Guide
Nano Pro Stainless Steel Color Engraving Guide

Nano Pro can be used for color engraving tests on stainless steel materials. By adjusting parameters such as power, speed, interval, and number of passes, different color effects can be achieved on stainless steel surfaces.

This article introduces the principles of stainless steel color laser engraving using Nano Pro, parameter testing methods, layered engraving workflow, and important precautions. By adjusting power, speed, interval, and passes, different color effects can be achieved on stainless steel surfaces.

1. Principle of Laser Color Engraving

The technical principle of color laser engraving varies depending on the material, but it mainly relies on two core methods: one is generating color naturally through oxidation reactions; the other is achieving the desired color effect through coloring agents.

For stainless steel color engraving, the technology is mainly divided into two categories. The first is that the laser beam instantly heats the metal surface, triggering physical or chemical reactions with the surrounding environment, thereby changing the surface color. The second is that the laser forms colored oxides on the metal surface or generates a transparent oxide film, producing various colors through thin-film interference effects.

By precisely adjusting key parameters such as laser power, engraving speed, interval, and passes, the reaction depth on the metal surface can be effectively controlled, achieving various color effects to meet different process requirements.

2. Stainless Steel Color Engraving Parameters

2.1 How to Test Different Color Parameters on Stainless Steel Using Nano Pro

The color engraving parameters in this example are based on the LONGER Nano Pro model, using stainless steel as the material.

With the "Material Test" function in LightBurn, the preparation of engraving parameter test files is greatly simplified. Users only need to enter the relevant parameter ranges in the "Material Test Generator" to automatically generate the test file. Key parameters include Power, Speed, Interval, and Passes. The combination of these parameters directly affects the final engraved color. By setting appropriate parameter ranges according to the material size, the corresponding test file can be generated.

The operation process is shown in the figure: first, start LightBurn, import the configuration file, select the correct serial port, and load the Nano Pro machine configuration. When the console displays "Nano Pro connected successfully," click "Laser Tools" in the toolbar to continue.

In the second step, after clicking "Laser Tools," select "Material Test." A matrix parameter setting interface will appear. Set the required matrix parameters in this interface. For Nano Pro, the recommended parameter range is Power 50%–100%, Speed 1000mm/min–3000mm/min, with an 11×11 matrix layout. After confirming the settings, click "Start" to begin the engraving test.

After completing the test, a color matrix will be generated. Users can select the desired color and find the corresponding power and speed parameters. The horizontal axis represents power, and the vertical axis represents speed. By matching the coordinates, the required settings can be determined.

2.2 How to Engrave a Color Artwork

Open LightBurn, click File → Import to load the layered image file, then connect to the Nano Pro machine.

After importing the image, perform layer processing on the vector graphic:

1) Select the vector section to be engraved.

2) Click the lower right corner and assign it to Layer 1.

3) As shown in the figure below, we set the butterfly section as a layer.

4) Then assign it to Layer 2.

5) Select the inner part of the butterfly.

6) Assign it to Layer 3.

After completing the layer separation, assign the corresponding color parameters to each layer. Once finished, start engraving to obtain the desired color result.

The final result is a blue butterfly.

3. Notes for Nano Pro Stainless Steel Color Engraving

3.1 Minimum Power

Important: When engraving stainless steel with Nano Pro, the power must remain above 50%. Power below 50% will result in very light coloration, mainly producing a single yellow tone. Engraving results are closely related to laser power, so precise adjustment is essential for achieving the desired color.

3.2 Minimum Stainless Steel Thickness and Surface Finish

During engraving, stainless steel plates that are too thin may deform due to heat accumulation. It is recommended to use stainless steel plates with a thickness of no less than 2 cm. Matte or brushed stainless steel surfaces are recommended for better engraving results. Industrial-grade or mirror-finish stainless steel is not recommended.

Common stainless steel surface finishes are shown below.

3.3 Ensure Level Positioning During Engraving

When using the recommended engraving parameters, ensure accurate laser focus and keep the Nano Pro machine level. Incorrect focus height will directly affect color uniformity and accuracy. Therefore, always calibrate the focus height before each operation.

Conclusion

By following the above methods, color engraving can be achieved on stainless steel using Nano Pro. Proper parameter testing, correct layer setup, and attention to power and material requirements are the key factors for obtaining stable color results.

By Laser Engraver Blogs | March 5, 2026
Nano Duo  Batch Fill Guide for Efficient Multi-Object Engraving
Nano Duo Batch Fill Guide for Efficient Multi-Object Engraving

Introduction

The Batch Fill function is designed to improve engraving efficiency by automatically identifying and copying a selected pattern onto multiple materials with similar contours. Using the camera to capture and recognize material outlines, the system replicates the design across all qualified objects in a single operation, ensuring consistent positioning and alignment.

Material Requirements

To ensure accurate recognition and proper batch placement, materials must meet the following conditions:

  • All materials must be identical in shape, color, and material type.

    • Dimensional variation between targets must not exceed 10%.

    • Area variation must not exceed 25%.

  • The material color must be clearly distinguishable from the background for accurate contour detection.

  • Triangles and pentagons are not supported.

  • Materials with highly reflective or glossy surfaces are not recommended.

  • At least two or more materials must be placed within the effective engraving area.

    • Minimum spacing between objects must be 5 mm.

  • Material thickness must be less than 5 mm.

Precautions Before Use

  • Ensure the camera function is operating properly before starting.

  • Select the specific element(s) you want to batch fill.

    • The system will automatically remove any unselected elements before performing the batch operation.

  • You must manually place the first pattern onto one material surface.

    • The batch fill process will replicate this pattern based on its position and angle.

  • Keep the base plate clean, free of debris, dust, or scratches to ensure accurate detection.

Batch Filling Process

1. Place the Materials

  1. Place materials of the same size, shape, and color on the base plate.

    • Maintain spacing greater than 5 mm between objects.

  2. Ensure all materials are positioned within the effective engraving range.

  • Figure 1: Correct placement

  • Figure 2: Incorrect placement – objects too close together

  • Figure 3: Incorrect placement – objects overlapping

  • Figure 4: Incorrect placement – objects of different shapes

2. Capture Material Image

  • Click Capture to take a photo of the materials and generate the contour outlines.

3. Set the Design Position

  1. Create or import your design on the canvas.

  2. Drag the design onto one material, ensuring it is fully positioned within the material boundary.

4. Batch Copy and Place Patterns

  • Select the positioned design and click Batch Fill.

  • The system will automatically detect the remaining material outlines.

  • The design will be copied to each recognized object at the same relative position and angle.

5. Start Engraving

  1. Adjust the appropriate material parameters.

  2. Follow the normal engraving workflow.

  3. Start the job to engrave all patterns on the canvas simultaneously.

By Laser Engraver Blogs | March 4, 2026
How to Use the Camera on the Nano Duo in LightBurn
How to Use the Camera on the Nano Duo in LightBurn

Introduction

This guide explains how to use and calibrate the built-in camera function of the Nano Duo in LightBurn. Proper camera calibration ensures accurate visual positioning, improves engraving precision, and minimizes alignment deviations between the on-screen design and the actual engraved result.

Required materials: red cardstock, calibration card.

1. Open the LightBurn software, connect the Duo device, and then click Galvo Engraving Mode → BL 450 nm. (The connection is considered successful only if the following device information is displayed in the console.)

The above applies to versions below 2.0.00

The above applies to versions 2.0.00 and above.

2. Click Laser Tools → Calibrate Camera Lens in the upper left corner.

The above applies to versions below 2.0.00

The above applies to versions 2.0.00 and above.

3. Once you are on the Calibrate Camera Lens homepage, select USB Camera (the built-in camera).→ Standerd Lens→Next

The above applies to versions below 2.0.00

The above applies to versions 2.0.00 and above.

4. After proceeding to the next page, capture the images in the order of ①②③④ shown in the top left image, repeating this process nine times in different directions before proceeding to the next step of visual alignment. (If you proceed directly to visual alignment without performing visual calibration, engraving deviations may occur.)

Error demonstration: Overexposure, too bright

Correct demonstration

5. The following message indicates that the visual calibration operation has been completed. Please click "Align Camera" to enter the visual alignment page.

(1) The first method to access the visual alignment page

(2) The second method to access the visual alignment page

6. Remove the calibration card here, then select USB Camera (the built-in camera) and click Next.

7. In the parameter settings page, the necessary parameters to adjust are Fill Speed and Fill Power, as well as Line Speed and Line Power.7. After setting up, click Frame Start, and then click Next when the sculpting is complete.

8. On this page, click Capture Image Next.

9. Double-click the center point of the graphic in the order of 1, 2, 3, 4 until it looks like the second image, then click Next.

10. The following message indicates that the visual alignment operation has been completed.

11. Finally, verify if there are any obvious deviations, then return to the creation pageWindowCheck Camera Control, and in the Camera Control page, select the camera moduleUpdate Overlay

The above applies to versions below 2.0.00

The above applies to versions 2.0.00 and above.

12.Import the carving material, place it on the carving area in the canvas, and then click Frame (to confirm the carving position) Start (to start carving).

13. After the carving is complete, click "Update Overlay" again to check if the carved position on the canvas matches the actual carved position. A deviation of 0.5-1 mm is normal. If the deviation is large, you need to repeat the visual alignment operation in step 7 above.)

By Laser Engraver Blogs | March 3, 2026
Ray5 Series — Offline Engraving Using TF Card
Ray5 Series — Offline Engraving Using TF Card

This guide explains how to perform offline engraving on the Ray5 series laser engravers using a TF card. Users can save GCode files to the TF card and perform standalone engraving through the control box without connecting to a computer. This tutorial applies to different Ray5 models, although interface layouts are different between old and new models.

1. Prepare Engraving File

First, save the engraving file in GCode format (.gc or .nc) to the TF card.
Users can design patterns using LightBurn and export the GCode file directly to the TF card.

2. Start Offline Engraving

Insert the TF card into the Ray5 control box and press File to access the TF card file list, then select the imported GCode file.

Enter the engraving preparation interface and click Frame to verify the engraving boundary.

After confirming the working area, press Start Engraving to begin engraving.

Note: Interface layouts are different between old and new models.

3. Model Version Differences

Old Version Ray5 (no air pump interface above the touchscreen)

New Version Ray5 (air pump interface located above the touchscreen)

Conclusion

The Ray5 series supports standalone engraving through TF card offline mode. Properly preparing GCode files and confirming the engraving boundary before starting helps achieve stable and reliable engraving results.

 

Video Tutorial

By Laser Engraver Blogs | February 28, 2026
How to use Longer Ray5 Mainboard as ESP32 module
How to use Longer Ray5 Mainboard as ESP32 module

The Longer Laser Engravers are equipped with a powerful ESP32-based mainboard, which can offer high computing speeds and advanced features such as WiFi, Touchscreen Display, microSD slot and so on. In particular, Longer Ray5 has an MKS LTS mainboard, which offers excellent engraving speeds with precise adjustment of the laser module's power.

One of the main risks for the mainboard of Longer Laser Engravers is to manually move the motor axes. This action, in fact, generates a current that goes from the motors to the mainboard, damaging the stepper drivers irreparably. When this happens, the mainboard can no longer move the axle motors, and must be replaced. However, as mentioned before, the mainboard is based on ESP32, and therefore even if it is no longer suitable for use with Longer Ray5, it can still be useful for other projects.

The fact that the heart of the system is an ESP32 completely changes the perspective in the event of a driver failure. In a traditional mainboard, damage to the stepper drivers would mean total death of the component. With ESP32, on the other hand, we are faced with an open and versatile architecture that keeps its computational value intact. So even though the power section of the MKS LTS is compromised and can no longer handle PWM signals for the Longer Ray5 motors, the onboard microcontroller remains an amazing asset.

As with Arduino, ESP32 can also be programmed according to what you need most; it is possible, for example, to create an RF receiving station, a home automation control system, an anti-theft system, and so on. The only thing you need is writing proper C++ code.

Unlike a ready-to-use ESP32 board, on MKS LTS the pins are not directly indicated and ready to use, but must be identified among the various pins of the mainboard, as they are connected to the different functions in the design phase. For individuals, just use a function like:

int pins[] = {2, 4, 5, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 25, 26, 27, 32, 33};

int numPins = sizeof(pins) / sizeof(int);

 

void setup() {

  Serial.begin(115200);

  delay(1000);

  Serial.println("--- ACTIVE INVESTIGATOR MODE ---");

  Serial.println("Connect a wire to GND and tap the pins one at a time.");

 

  for (int i = 0; i < numPins; i++) {

    // We use INPUT_PULLUP for pins that support it

    // Note: 34, 35, 36, 39 don't have internal pullups, we will test them too

    if (pins[i] < 34) {

      pinMode(pins[i], INPUT_PULLUP);

    }

  }

}

 

void loop() {

  for (int i = 0; i < numPins; i++) {

    // If the pin reads LOW, you are touching it with GND

    if (digitalRead(pins[i]) == LOW) {

      Serial.print("FOUND! The pin you're tapping is the GPIO: ");

      Serial.println(pins[i]);

      

      // Wait for the wire to disconnect so as not to clog the serial

      while(digitalRead(pins[i]) == LOW) { delay(10); }

      Serial.println("---------------------------------------");

    }

  }

}

At this point, simply connect the respective pins to GND via a 10k pull-down resistor for safety, and the pin-detected will appear on consoles.

However, at the end of the detection procedure (which will take several hours) the available result pins are only these shown in the figure:

That is, the pins are available:

GPIO Main Function Usage notes

2 I/O Connected to Probe.

4 ADC2_CH0 / Touch General Purpose. Great for CSN - SPI communication.

18 VSPI SCK Great for SPI communication.

19 VSPI MISO Great for SPI communication.

23 VSPI MOSI Great for SPI communication.

33 ADC1_CH5 / Touch 8 General Purpose. Great for GDO0.

34 ADC1_CH6 Hardware pull-ups. Input only. 3.3V always present.

35 ADC1_CH7 Hardware pull-ups. Input only. 3.3V always present.

36 ADC1_CH0 Hardware pull-ups. Input only. 3.3V always present.

13 ADC2_CH4 HSPI communication connected to microSD.

14 ADC2_CH6 HSPI communication connected to microSD.

15 ADC2_CH3 / Strapping HSPI communication connected to microSD.

39 Solo Input Great for ADC1 but connected to microSD.

The GPIOs available are some of the best in ESP32, as you can use the SPI protocol with them, which allows you to do many useful things, such as using a CC1101 RF chip.

With the well-known GPIO pins, even a damaged MKS LTS becomes a valuable resource, to be used in a thousand different ways and just as many fun projects.

 

By Laser Engraver Blogs | February 25, 2026