4 Laser Engraving Problems and Solutions

Most Common Laser Engraving Problems and Their Solutions

The versatility of laser engraving machines has completely changed the world of customization and personalization. Artisans can do everything from engraving intricate designs on jewelry to creating logos on promotional materials. However, every technology can have drawbacks, which is why it always helps to have a guide that outlines common laser engraving problems and solutions. We’ve designed this article to address common laser issues you may encounter as you continue working with laser engravers.  

Problem 1: Inconsistent Engraving Depth

An issue that can arise for even the most experienced engravers is inconsistent laser engraving depth. That causes some parts of your etchings to become deeper, making them appear uneven. This often happens when you try to engrave on material with an uneven surface. A laser beam can have difficulty maintaining consistent depth throughout the engraving process if the material is not flat or has variations in thickness. 

You can also face problems if you don’t have the laser engraving machine’s focus set correctly. That causes the laser beam to diverge (separate) or converge (join), resulting in engraving depth variations. The laser’s power and speed settings can also affect engraving depth. The laser may not penetrate the material deeply enough if the power is too low. Setting it too high can lead to the laser going too far into the material. 

Solution: Calibrate Focal Length and Power Settings

Start by checking the laser engraving speed and power settings on your machine’s control board. Consider whether you’re looking to do deeper engraving or want shallower etching. Add more power to your laser configuration to achieve deeper engravings. Make sure your laser lens is clean so that it doesn’t cause variations when the laser beam passes through. 

Look for the focus settings on your machine, which could consist of a focus gauge or an autofocus feature. Use that to achieve the correct focal point for your chosen material. Finally, ensure your material is flat and securely positioned to prevent movement during engraving.  

Problem 2: Burn Marks on Engraved Surfaces

Burn marks on the surface of your application often detract from the visual appeal and quality of an engraving. They often occur because of excessive heat generated during engraving. Insufficient ventilation in your laser engraving machine can cause heat buildup, leaving burn marks on your material. 

Incorrect power settings can also lead to burn marks. You could burn or scorch your material if your laser head settings are too high. The quality of the material plays a part as well. Etchings performed on low-quality materials or those with high resin content can lead to burn marks. 

Solution: Optimize Speed and Power Parameters

Try lowering your power settings and increasing engraving speeds to prevent burn marks. If that doesn’t produce the desired result, experiment with different settings to find the right balance to achieve optimal engraving depth while preventing burns. Use the following laser engraving tips to optimize your settings.

  1. Pick suitable material.
  2. Look at the material guidelines.
  3. Calibrate your machine by checking the focus, beam alignment, and machine condition.
  4. Start with a lower laser power and higher speed setting to reduce the risk of burning or charring.
  5. Check to see that your control transformer is correct for your machine.
  6. Make gradual adjustments to power and speed, then observe the results. 
  7. Record your findings for different materials until you achieve the correct settings.
  8. Observe what settings your laser tube needs to achieve special effects like deep engraving to add texture or lighter surface etchings.

Check the quality of your materials to ensure they are suitable for laser engraving. You can do that by:

  • Looking at the material data sheet specifications
  • Using non-organic materials with a lower resin content
  • Watching how the material’s surface reacts to the laser

Problem 3: Unwanted Charring or Darkening

Organic materials like wood and paper can end up charring because of the excessive heat generated by your laser machine. Engravers also must deal with the unique challenges of organic materials because of the variations in quality and moisture content. You’re more likely to see charring occur with dry or low-quality wood. 

Solution: Adjust Speed and Air Assist

You can reduce charring and darkening by slowing down the engraving speed. Slower speeds let you focus the laser on one spot for extended periods, reducing the heat generated. Try decreasing the engraving speed by 10% to 20%. Run an engraving test on the material and see if that results in less charring and darkening. Slowing down your laser can lead to deeper engravings, so adjust other settings as needed. 

Laser engraving systems typically have an air assist system that blows air over your engraving material. That’s done to remove smoke and debris, reducing the chances of charring. Increase the air assist pressure or flow rate if you have problems with darkening or charring. Make sure the air nozzles are clean and free of obstructions. Look at your laser engraving machine’s manual to see if it allows you to manually adjust the air pressure or flow rate. 

Problem 4: Misaligned Engravings

Misalignments in engraving projects occur when issues with the laser path lead to crooked or skewed engravings. That often happens because of problems with a laser engraving machine, like a loose belt or crooked mirrors. Calibration issues may also lead to misalignments because of incorrectly configured software. If material shifts during the engraving process, that can cause the design to not appear in the correct location. 

Solution: Proper Material Positioning and Alignment

You can avoid misalignment issues by positioning your material in the engraving bed with clamps or any method that keeps it from moving, and make sure it’s aligned correctly before you start engraving. You should also check the software settings and make sure they are calibrated to your laser engraving machine. 

Finally, perform regular maintenance on your device to ensure all components, like the magnetic switch, remain in working order when needed. That way, you can avoid issues like:

  • Bad contact because of a loose high-voltage line
  • Motor failure
  • Blown control transformer
  • Ground wire not properly set

Ensure Consistent Quality With the Right Laser Engraver Machines

The precision and power provided by OMTech Lasers make them suitable for various engraving projects. Click here to browse our inventory and find a machine flexible enough to accommodate your needs.