The RF Laser Tube (Radio Frequency laser tube) source enables precise frequency modulation, allowing users to adjust the laser’s pulse frequency directly within the LightBurn software. This capability offers a dynamic range of control over the laser's interaction with various materials. The modulation of frequency significantly influences the energy distribution, thermal effects, and material response during engraving, providing a versatile platform for diverse crafting applications and outcomes. This article will guide you on how to change RF Laser Tube frequency for precise engraving.
1. What is Frequency?
Frequency refers to the number of laser pulses emitted per second, measured in Hertz (Hz). In RF laser tubes, the laser operates by rapidly turning on and off (pulsing), and the frequency determines the speed of these pulses.
Low Frequency:
- Fewer pulses per second, but each pulse delivers more concentrated energy.
- Better suited for deep cutting or processing materials due to higher energy density.
High Frequency:
- More pulses per second, but each pulse carries less energy.
- Ideal for fine engraving or reducing surface damage to materials.
2. How Frequency Interacts with Materials
Low Frequency (e.g., 1-5kHz):
- Longer intervals between pulses allow materials to cool slightly between pulses.
- Suitable for cutting thicker materials like wood or leather, where deep penetration is needed.
Learn more: Leather Laser Engraving - A Complete Guide for Beginners
Medium Frequency (e.g., 5-20kHz):
- Shorter intervals between pulses provide balanced energy distribution.
- Ideal for materials like plastics or thin metals that need clean cuts and moderate depth.
High Frequency (e.g., 20-50kHz or more):
- Very short intervals between pulses distribute heat more evenly.
- Best for engraving delicate materials like glass or acrylic to minimize cracks or damage.
- Reduces burn marks on organic materials like fabric or paper, better for thin materials or precision cuts.
3. Practical Comparisons
Engraving:
- Low Frequency: Produces deeper engravings but may result in rougher or charred surfaces.
- High Frequency: Creates shallow, clean, and smooth engravings.
Cutting:
- Low Frequency: Cuts deeper and is more effective for thick materials.
- High Frequency: Results in cleaner edges.
4. Key Considerations
- Material Sensitivity: Softer or heat-sensitive materials (e.g., paper, fabrics) generally perform better at higher frequencies to reduce burn marks.
- Cutting vs. Engraving: Lower frequencies are often better for cutting as they deliver more energy per pulse.
- Machine Capabilities: Ensure your laser engraving machine is capable of safely operating at the chosen frequency range.
5. Comparison of CO₂ Glass Tube (DC-Excited) vs RF CO₂ Tube:
| Aspect | CO₂ Glass Tube (DC-Excited) | RF CO₂ Tube (Radio Frequency) |
| Frequency Range | Typically 10 Hz to 1 kHz. Limited by the DC excitation mechanism. | Much higher, typically 1 kHz to 100 kHz or more, allowing precise control. |
| Pulse Control | Limited control with slower response times. | Precise and rapid pulse modulation for enhanced performance. |
| Energy Per Pulse | Higher energy per pulse due to lower frequency, suitable for deeper cuts. | Lower energy per pulse at higher frequencies, enabling smooth and delicate engraving. |
| Beam Quality | Less consistent, with potential fluctuations in intensity. | More stable and uniform, resulting in consistent cutting and engraving quality. |
| Material Interaction | Best for cutting thicker materials like wood and leather, but less suitable for fine detail. | Ideal for intricate engraving and cutting on heat-sensitive or thin materials. |
| Heat Affected Zone (HAZ) | Larger HAZ due to longer pulse duration and slower pulse rates. | Smaller HAZ due to faster pulsing, reducing material damage. |
| Speed | Slower cutting and engraving speed due to limited frequency range and slower pulse modulation. | Faster processing speed, especially for engraving, due to higher frequency and precise pulse control. |
| Applications | General-purpose cutting; less effective for detailed engraving. | Advanced engraving and cutting where precision and fine detail are required. |
| Cost | Lower upfront cost but shorter lifespan (~3,000–5,000 hours). | Higher cost but significantly longer lifespan (~30,000 hours) and lower maintenance. |
| Thermal Effects | Higher risk of overheating or charring, especially on delicate materials. | Minimal thermal impact, allowing clean edges and smooth surfaces. |
| Flexibility | Limited in application range due to slower pulse control. | Highly versatile, with adjustable frequency enabling fine-tuned results for various materials. |
Learn more: RF CO2 Laser Vs Glass Tube CO2 laser - Which Better?
6. How to Adjust RF Laser Tube Frequency in LightBurn
Step 1: Access Machine Settings:
- Open LightBurn and connect to your laser.
- Navigate to “Edit” > “Machine Settings”.
Step 2: Locate Frequency Settings:
Look for the “Laser Control” or “Advanced” tab where the frequency or PWM (Pulse Width Modulation) settings are configured.
Step 3: Input Frequency Range:
Enter the desired frequency value within the allowable range (For OneLaser customized 38W RF Laser tube from 0–25,000 Hz, we normally suggest no lower than 25 Hz).
Step 4: Test and Apply:
After adjusting, save the changes and test on scrap material to ensure the setting achieves the desired result.
Summary:
This flexibility in frequency settings opens up a variety of creative possibilities, allowing precise customization of texture, depth, and detail in laser engraving projects. Additionally, the ability to fine-tune these parameters supports the exploration of advanced applications in industrial and artistic contexts, highlighting the importance of frequency modulation as a key factor in laser material processing.
