FAB ACADEMY 2025

Computer Controlled Cutting

brief Insight of this week

In our group assignment, we explored the laser cutter and learned about its process. We gained insights into how the laser cutter works, from the preparation of the design to the actual cutting process. Additionally, we understood how to create parametric designs and how these designs can be translated into the laser cutter for precise and efficient cutting. The experience helped us grasp the importance of accuracy in the design phase and the capabilities of laser cutting in bringing complex designs to life.


About Laser Cutter

A CO2 DC glass laser tube is a type of laser used in laser cutters, particularly for cutting and engraving a variety of materials. The "CO2" refers to carbon dioxide, which is the gas used in the tube to generate the laser beam. These tubes are commonly made of glass, which helps to contain the laser gas and facilitate the laser's efficient generation. The laser operates by exciting the CO2 gas with a high-voltage electrical discharge, producing a laser beam with a wavelength of around 10.6 microns. This wavelength is highly effective for cutting and engraving materials like wood, acrylic, leather, glass, and even some metals.
Key benefits of CO2 glass laser tubes include:

  • Precision: - They offer high accuracy and fine detail for intricate designs.
  • Versatilit: - These lasers can cut or engrave a wide range of materials.
  • Efficiency: - CO2 lasers are known for their energy efficiency and ability to cut through thick materials with high power output.
  • Cost-effectiveness: - Glass CO2 lasers are typically more affordable compared to other types of laser tubes, making them popular for small to medium-scale applications.


    Overall, CO2 glass laser tubes are widely used in industries such as manufacturing, signage, crafting, and prototyping for their ability to deliver clean, precise results across a variety of materials.


    Group Assignment

    The purpose of the group assignment is to: -

  • Understanding the Operation and Specifications of Laser Cutting Machines : - Develop a thorough understanding of laser cutting machines, focusing on their key components, operational principles, and the specific ways they are utilized for precise cutting across a variety of materials.
  • Generating G-Code for Laser Cutters :- Learn how to generate G-code specific to laser cutting machines, including the commands and parameters needed to control the laser's movement, intensity, and cutting paths.
  • Understanding the Laser Cutting Process : - Study the principles behind laser cutting, including the role of laser technology, the types of lasers used, and how the laser interacts with materials to achieve clean, accurate cuts.
  • Calculating Speed and Kerf in Laser Cutting : - Learn how to calculate the optimal cutting speed and kerf for laser cutting, considering factors like material type, thickness, and laser power to achieve the best quality cuts.
  • Understanding Power and Speed Testing in Laser Cutters : - Study how to test and measure the power and speed settings on laser cutting machines, and understand how adjusting these parameters affects cutting quality, efficiency, and material integrity.






    Key Safety Tips for Operating a Laser Cutting Machine

  • Wear Appropriate Protective Gear: - Always wear safety goggles or glasses designed for laser protection to shield your eyes from harmful laser radiation. Additionally, use gloves and flame-resistant clothing to protect your skin from burns and other injuries.
  • Check Equipment Condition: - Before operating the machine, inspect the laser cutting system for any signs of wear or malfunction. Make sure all safety features, such as emergency stop buttons and protective covers, are functioning correctly.
  • Maintain a Clean Work Area: - Keep the workspace clear of clutter and flammable materials. A clean environment helps to avoid potential hazards like fires or accidents caused by obstructed equipment.
  • Ventilation and Airflow: - Laser cutting processes can generate harmful fumes and gases. Ensure the area is well-ventilated, and if necessary, use an exhaust system to direct fumes away from the operator and the workspace.
  • Avoid Direct Exposure to the Laser Beam: - Never look directly at the laser beam, even with protective glasses, and never point it toward anyone else. Always keep a safe distance from the laser cutting area.
  • Ensure Proper Material Handling: - Verify that the materials being cut are suitable for the laser machine and do not emit toxic gases when heated. Be cautious when handling flammable materials or highly reflective surfaces.
  • Fire Extinguisher Accessibility: - Keep a fire extinguisher nearby, and make sure it is appropriate for the types of materials being cut (e.g., CO2 extinguishers for electrical or flammable material fires).
  • Monitor the Cutting Process: - Do not leave the machine unattended while it is operating. Continuous monitoring allows quick response in case of malfunction or an emergency.





    Understanding the Operation and Specifications of Laser Cutting Machines

    Laser cutting machines operate by focusing a laser beam onto the material to be cut. The laser is typically generated by a laser source, such as CO2 or fiber lasers, and then directed through a series of mirrors or fiber optics to the cutting head. The cutting head focuses the laser beam onto the material’s surface with extreme precision. As the laser beam interacts with the material, it heats it to a point where it either melts, burns, or vaporizes, depending on the material type. Simultaneously, a jet of gas, typically oxygen or nitrogen, is often used to assist in the cutting process by blowing away the molten material and ensuring a clean edge. The material is typically placed on a moving bed or stage, and the laser cutting machine's computer-controlled system (CNC) moves either the material or the laser head along pre-programmed paths to cut the material. The movement can be based on a vector or raster-based design, with the cutting path being determined by the file input from a CAD program. The result is highly detailed, accurate cuts with minimal kerf (the width of the cut).





    Understanding the Laser Cutting Process

    The laser cutting process is a highly efficient and precise method used to cut and engrave materials using a focused laser beam. It is commonly used in industries like manufacturing, automotive, aerospace, signage, and fabrication due to its ability to deliver accurate and clean cuts. Here’s a breakdown of how the laser cutting process works and the steps involved:

    Laser Generation

  • 1. The process begins with the generation of a laser beam. There are two main types of lasers used for cutting:

    I. CO2 lasers (carbon dioxide) are commonly used for non-metal materials, such as wood, plastics, and acrylics.
    II. Fiber lasers are more efficient and powerful, often used for cutting metals like steel, aluminum, and brass.

  • 2. Focusing the Laser Once the laser is generated, it is focused through a series of mirrors or fiber optics and directed towards the cutting head. The cutting head contains a lens that focuses the laser beam into a very fine point. The precision of this focused beam is crucial for achieving clean and accurate cuts.

  • 3. Material Interaction When the focused laser beam makes contact with the material, it heats it to a very high temperature. The material undergoes one of the following processes depending on the laser's power, the material type, and the cutting settings:

    I. Melting: The material melts away at the cut point, allowing the laser to cut through it.
    II.Vaporization: In some cases, the intense heat causes the material to vaporize directly into gas, leaving a clean cut with minimal residue.
    III. Burning: For materials like metals, the laser can burn through the material by oxidizing it, assisted by oxygen or other gases. The cutting process produces a very precise and narrow cut, often with minimal kerf (the width of the cut), which reduces material waste and increases cutting efficiency.

  • 4. Assist Gas During the cutting process, assist gases (such as oxygen, nitrogen, or compressed air) are often used to help in the cutting and cleaning process. These gases:

    I. Oxygen: Often used for cutting steel and other metals, oxygen helps with the oxidation process, which speeds up the cutting and leaves a rougher edge.
    II. Nitrogen: Used for cutting metals like stainless steel and aluminum, nitrogen helps to create a cleaner edge by preventing oxidation.
    II. Compressed Air: Used for non-metallic materials, compressed air helps blow away debris and molten material from the cutting area.

  • 5. Motion Control The cutting process is computer-controlled (CNC - Computer Numerical Control), which means the path of the laser is determined by a digital file (usually a CAD or CAM design). The cutting head or the material itself moves along the pre-programmed path. This allows for complex shapes, intricate patterns, and detailed cuts to be made with precision. The movement can be in multiple axes (usually X, Y, and Z) depending on the complexity of the design.

  • 6. Cooling and Waste Management Laser cutting generates a lot of heat, so cooling systems are often employed to maintain the optimal working temperature of the machine. This helps protect components like the laser source and cutting head from overheating. Additionally, a vacuum or air jet can be used to blow away debris, molten material, and smoke, ensuring that the cut remains clean and that the machine operates efficiently.

  • 7. Finishing Once the material is cut, the finished product may require some post-processing. This can include removing protective coatings, cleaning edges, or adding finishes to improve the surface quality. In some cases, the cut edges might need to be polished, especially if high-quality aesthetics are required, or if a smooth edge is critical to the product’s functionality.



    Peramectric Design Cutting Process



    STEP 1:

    Initially, a standard clearance of 6mm is maintained between the nozzle head and the workpiece.

    STEP 2:

    After that, the cardboard is placed into the laser cutter, and the final design start for printing.


    STEP 3:

    Next, the design is precisely cut into the final shape on the cardboard.

    STEP 4:

    Then, we carefully and easily remove the design from the cardboard, ensuring that all parts are fully detached without any damage.


    STEP 6:

    STEP 5:

    Afterward, our final design is properly printed and ready for preparation. We then begin the process of assembling the pieces together.






    Understanding Power and Speed Testing in Laser Cutters

    Power and speed testing in laser cutters is essential for optimizing cutting performance. The power determines the intensity of the laser beam, affecting how deep the cut is, while speed controls how quickly the laser moves across the material. Testing different combinations of power and speed helps identify the best settings for achieving clean cuts, minimizing material damage, and ensuring efficiency. A slower speed with higher power is often used for thicker materials, while faster speeds with lower power are effective for thinner materials. Properly adjusting these parameters helps achieve the desired results in terms of cut quality and material preservation.





    Laser cutting power and Speed test

    Initially, we conceptualized and planned the laser cutting design. The design was then created in SolidWorks and saved as a DXF file format. To transfer the design to the laser cutting machine, we used RDWorks software, where we imported the DXF file. After importing, we thoroughly examined the design within RDWorks, gaining an understanding of its features and functions. Next, we applied specific offsets and set distinct power, speed, scan, and cut parameters for each cut type, color-coding each section for clarity. In the end, the file was finalized and ready for input into the laser cutting machine.





    Speed Pattern Test Sheet Printing on Cardboard







    Kerf Masurement

    Kerf measurement refers to the process of determining the width of the material that is removed during the laser cutting process. This measurement is crucial for ensuring precision, as the kerf can affect the final fit and alignment of parts. Factors such as laser power, speed, and material type can influence the kerf width. By accurately measuring the kerf, adjustments can be made to compensate for the material loss, ensuring a more precise and accurate cut for each piece.




    Analysis Kerf Calcuation

    We designed a 100 mm by 100 mm speed pattern box. For the cutting process, we set the laser cutter to a power of 70 and a speed of 30. With these settings, the laser was able to cut the box cleanly and accurately. The combination of high power and low speed helped ensure a precise and complete cut through the material.




    After cutting the speed pattern box using the laser cutter, we measured the dimensions using a Vernier Caliper. Based on the measurements, we calculated the kerf — the amount of material removed by the laser during the cutting process.

    After measuring with the Vernier Caliper, we observed that the original dimensions of our speed pattern box, which were 100 mm × 100 mm, had been reduced to 99.30 mm × 99.30 mm after laser cutting. This indicates a material loss of 0.70 mm during the cutting process. As a result, the actual size of the box is now 99.30 mm, and the kerf (material removed by the laser) is calculated to be 0.70 mm.







    Conclusion

    This assignment has provided valuable learning experiences in several key areas. First, I gained a deeper understanding of the laser cutting process, from design creation in SolidWorks to preparing the file for the machine using RDWorks. I learned how to adjust parameters such as power, speed, and offsets to optimize the quality of the cut. Additionally, the importance of accurately measuring kerf and testing different settings was highlighted, as it plays a crucial role in achieving precise results. Overall, this project improved my practical skills in laser cutting and design preparation, as well as my ability to troubleshoot and fine-tune the process for better outcomes.