Finding the focal point during laser welding is crucial for achieving precise and high-quality welds. However, many users encounter difficulties in identifying the correct focal point while operating handheld laser welders. This guide will walk you through the process of locating the focal point and provide troubleshooting steps for common issues. By following these methods, you can ensure accurate and efficient welding.
Main Causes of Focal Point Issues
When the focal point cannot be located during handheld laser welding, the most common causes include:
- Incorrect focus distance setting
- Burnt Protective Lens: Damaged protective, collimating, or focusing lenses can disrupt the laser beam’s focus.
- Loose QBH Connector: An improperly secured QBH connector leads to alignment issues.
- Incorrect Lens Installation: Using incorrect or improperly installed lenses can change the focal length or distort the laser beam.
How to Find the Focus Distance
Before diving into troubleshooting, let’s first review the standard procedure for locating the focal point:
- Adjust Laser Power:
- Set the laser power to approximately 300W for optimal visibility and safety during the adjustment process.
- Prepare the Equipment:
- Secure the ground clamp to ensure the safety mechanism is engaged.
- Adjust the Laser Gun’s Graduated Tube:
- Loosen the locking mechanism on the graduated tube (laser gun pipe).
- Test the Laser on Material:
- Activate the laser on the testing material while gradually adjusting the graduated tube’s position.
- Move the tube slowly until you observe the strongest and brightest beam, which indicates the focal point.
For a visual guide, refer to the instructional video linked in the equipment manual or online resources.
Troubleshooting When You Can’t Find the Focal Point
If the above steps fail to help you locate the focal point, there may be underlying technical issues. Here’s how to diagnose and resolve them:
1. Check for Burnt Protective Lens
Why This Happens:
- Prolonged use or exposure to impurities during welding can damage the protective, collimating, or focusing lenses. A burnt lens affects the laser’s ability to focus properly.
How to Resolve:
- Inspect each lens in the following order:
- Dual Protective Lens: Check for discoloration, cracks, or burns by holding the lens against a light source.
- Focusing Lens: Repeat the inspection for the focusing lens.
- Collimating Lens: Finally, examine the collimating lens for similar signs of damage.
- Replace any damaged lenses with new ones. Ensure you’re using high-quality, compatible components to maintain focus and laser output integrity.
2. Ensure the QBH Connector is Properly Secured
Why This Happens:
- A loose QBH connector prevents the laser beam from aligning properly with the optical system, leading to focal point issues.
How to Resolve:
- Perform the following steps:
- Hold the laser gun head with one hand and the QBH connector with the other.
- Gently twist the connector left and right to check for any movement.
- If there’s any looseness, disassemble the connector and reinstall it securely.
- Ensure the QBH connector is tightly locked in place to avoid misalignment during operation.
3. Verify Lens Compatibility and Installation
Why This Happens:
- Using the wrong lenses or installing lenses incorrectly can alter the laser beam’s focal length, making it impossible to find the focal point.
How to Resolve:
- Check the lens type:
- Ensure you are using the correct focusing lens and collimating lens for your laser welding application.
- Confirm proper installation:
- For correct assembly, the convex surfaces of both the focusing lens and collimating lens should face the reflecting mirror.
- If the lenses are installed backward, this will result in a distorted beam and incorrect focal point. Reinstall the lenses following the manufacturer’s guidelines.
Tips for Preventive Maintenance
To avoid future issues with finding the focal point, regular maintenance is key:
- Clean the Lenses Frequently:
- Use specialized lens-cleaning tools and solutions to remove dust, debris, and other impurities.
- Inspect the QBH Connector Regularly:
- Check the connector for looseness or wear and tear, and tighten it as needed.
- Store and Handle Lenses Carefully:
- Always store spare lenses in a clean, dry, and dust-free environment. Handle them with care to avoid scratches or other damage.
- Follow Manufacturer Guidelines:
- Refer to the user manual for specific instructions on maintaining your handheld laser welder’s optical system.
Further supports need from Rayno Laser
Locating the focal point is a fundamental step in using a handheld laser welder effectively. By following the standard adjustment procedure and addressing potential issues such as damaged lenses, loose QBH connectors, or improper lens installation, you can resolve most focal point problems quickly and efficiently.
Remember, regular maintenance and adherence to operational guidelines are essential for ensuring the long-term reliability and precision of your welding machine. If problems persist after following the troubleshooting steps, consider consulting a professional technician or contacting the manufacturer for support.
Mastering the art of finding the focal point will significantly enhance your welding precision, resulting in stronger, cleaner, and more reliable welds.
