Health and Safety
As well as the standard health and safety procedures when using any machine, Laser cutting has specific risks.
- The laser. It uses a CO2 laser that can cause permanent damage even when not looking directly into the beam. It is after all designed to burn through things. It is absolutely forbidden to remove or tamper with any of the interlocks that prevent the laser being disabled when the case is open. The windows on the cutter will protect from any scattered UV radiation though the light may be uncomfortable when it hits the metal support grid. Do not try to view the cut through the ventilation holes in the side of the machine.
- Toxic fumes. The laser works by burning away material. This results in the release of fumes which can be unpleasant or hazardous. Some fumes can be extremely dangerous and materials that produce these fumes are not permitted to be used in any of the laser cutters. A list of approved materials can be found in the Material Selection chapter. You may not use any material other than those listed in that chapter without consultation with Makerspace directors.
- Fire. Some materials can support combustion. As the laser is quite literally burning the material away there is always a risk of fire. You may not run the laser cutter unattended. This means that you must be in the downstairs space (shark tank or workshop) and monitoring the cut. If there is fire, the first action is to stop the cut using the emergency stop button on the cutter. This will cut the power and remove airflow (blower and extractor). Any fire will usually self extinguish very quickly. or can be extinguished with a fireproof cloth. If the fire is not extinguishable without putting yourself at risk, follow the appropriate fire alarm procedure and evacuate the building.
- Mechanical components. The cutter head is moved by motors that are powerful enough to cause damage to hands and other implements. Do not place hands or other tools inside the bed when the head is moving. These can cause damage to the machine, injury to persons and be messy to clean up.
- Noise. The cutter itself is relatively quiet but the associated chiller, air pump and extractor can provide a level of noise that is uncomfortable. The use of hearing protection is recommended if remaining in close proximity for prolonged periods.
Materials that must not be cut with a laser
| Laser Cutting Materials to Avoid | Reason |
|---|---|
| PVC | Melting releases toxic chlorine gas |
| Polycarbonate | Difficult to cut, absorbs most of the laser light.Discolors after laser cutting. |
| Coated Carbon Fiber | Resin coating releases toxic fumes on melting |
| Fiberglass | The glass refracts the laser light. Resin coating releases toxic fumes |
| Galvanized Metal | The zinc or nickel coating turns to dangerous volatile oxides. |
| ABS | Melting releases toxic cyanide gas |
| HDPE | Quickly catches fire |
| Polystyrene | Quickly catches fire |
Materials that can be cut with a laser
| Material | Notes |
| Acrylic sheet (perspex etc.) | Easy and simple to cut. Cuts by ablation (ie material vapourises) |
|
Polypropylene |
Can be tricky as it melts. Lots of small cuts instead of one big one |
| Styrene | Same as for Polypropylene |
| Foam (check the type) | Foams can be readily cut but do check that it is not pvc or similar. |
| Wood | Wood cuts by burning. Many small cuts can give a better finish than one big cut. Risk of fire. Different woods have different compositions so try on a sample first. MDF will vary widely depending on source. |
| Slate |
Can engrave but not cut |
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