3. Computer controlled cutting¶
Group assignment:
- Do your lab’s safety training
- Characterize your lasercutter’s focus, power, speed, rate, kerf, joint clearance and types.
- Document your work to the group work page and reflect on your individual page what you learned.
This week, we worked with two machines: a vinyl cutter and a laser cutter.
Laser Cutter¶
In our lab, the primary laser cutter is a Chinese CO2 laser cutter with CNC, with 80 Watts of power and a working area of 600x400mm.
| Feature | Specification |
|---|---|
| Country | China |
| Model | Kimian 6040 |
| Controller | RDC6445GZ |
| Laser Type | CO₂ |
| Laser Power | 80W |
| Work Area | 600mm x 400mm |
| Max Cutting Depth | 8mm-9mm |
| Supported Materials | Wood, Acrylic, Leather, etc. |
| Max Speed | 500mm/s |
| Cooling System | Water |
| Software Compatibility | RDWorks, Lightburn |
| File Formats | SVG, DXF, AI, PDF, etc. |
| Connectivity | USB, Ethernet |
| Power Supply | 220V |
Safety Measures¶
In our lab, we use a Chinese 80W CNC CO2 laser cutter with a working area of 600x400mm. This machine is an important tool for precise cutting and engraving, but it requires strict adherence to safety protocols to prevent potential hazards.
Safety Precautions and Training All students have been trained in the safety precautions and proper use of the laser cutter. During training sessions, we discussed the basic rules to avoid dangerous situations and respond to potential problems. Basic recommendations include:
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Supervision: Never leave the laser cutter unattended while it is operating.
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Fire extinguisher: Make sure a properly maintained and tested fire extinguisher is easily accessible.
- Air supply system: Always turn on the air supply system to reduce the risk of material combustion and improve the cutting quality.
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Air Filtration: Use air filters to minimize harmful fumes.
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Water cooling system: Turn on the water cooling system before starting the laser. The water temperature should not exceed 35 °C to prevent overheating.
Focusing¶
Focusing the laser on this laser cutter is done manually.
There’s a specific button, the Laser Switch, to turn on the laser.
In normal mode, if the button is activated, a regular red beam is emitted, which aids in laser focusing.
On the side of the laser cutter, there are two buttons for raising and lowering the table.
Using these buttons, the table should be adjusted so that the red beam is centered:
Measuring the kerf¶
We also measured the kerf of our Laser cutter. First we did a bit of research. The kerf is the portion of material that is burnt away by the laser beam. We learnt that the kerf depends on several factors, among them the focus and type of material.
We measured it for cardboard of approx. 3mm using this technique:
First, we designed and cut an array of small rectangles:
Then, we measured the width of the large rectangle remaining after removing the small rectangles:
Then, we measured the width of the small regtangles together:
The difference between the two measurements has then to be divided by the number of “beams” used to cut the rectangles:
$$\frac{100.47 - 97.92}{11} = 0.23\text{mm}$$
Therefore, our kerf = 0.23mm