Flux Laser Material List | Things You Can and Cannot Cut With a Diode Laser

When using a Flux laser or any diode laser, it is important to be aware of the materials you can work with, especially for the sake of safety. From engraving delicate patterns to cutting wood, the results are highly influenced by the material used.

This article aims to detail the materials that are best suited for laser cutting and those that are hazardous or completely prohibited. We will address critical questions such as “Is it possible to cut white MDF with a diode laser?” and “What should not be cut with a diode laser?”

Let’s get started.

What Materials are Good for Laser Cutting?  

Laser cutters such as those in the Flux series have a specific working range that differs in all makes and models. The type of materials the machine can work on is determined by the laser power and properties of the material. Outlined below are some basic and safe options for both cutting and engraving:   

✅ Recommended Materials for Laser Cutting:  

• Plywood & MDF (not white)  
• Acrylic (cast not extruded)  
• Cardboard & Paper  
• Natural Leather  
• Fabrics (certain types)  
• Rubber (must be marked as laser safe)  
• Softwood & hardwood  
• Anodized aluminum (only for engraving)  
• Glass (engraving only)  
• Slate and Stone (Inscriptions Only)  

The factors that determine your results greatly affect your laser power, speed settings, material thickness, and more. Generally, thinner and uniform surfaces yield better results.  

What Materials are Best Suitable for Diode Lasers?  

Compared to CO₂ lasers, diode lasers are relatively lower in power, making them most ideal for thin, easy to burn or engrave materials.  

👍 Recommended Materials for Diode Lasers:  

• Basswood  
• Balsa  
• Cardboard  
• Vegetable tanned leather  
• Felt  
• Black acrylic  
• Plastic (marked laser safe)  

Due to the wavelength, darker surfaces are preferential. Black acrylic as an example will always cut more cleanly compared to its transparent and white variants.

If you’re still asking yourself, “What material is best for a diode laser?”, the answer is dark, non-reflective, and thin organic materials such as wood and leather.  

What are the Best Fabrics for Laser Cutting?  

While laser cutting offers precision and detail, not all fabrics are easily accessible or safe for use.  

Best Fabrics:  

• Denim  
• Cotton  
• Felt  
• Silk  
• Linen  
• Polyester (case by case)  

Natural fabrics such as cotton and silk do not release harmful fumes when cut, and are clean cutting. When in doubt, always do a burn test or check with the manufacturer.  

Fabrics to Avoid:  

• PVC-coated materials  
• Vinyl  
• Chlorinated synthetic leather backing  

These pose the risk of releasing toxic gases, such as hydrochloric acid, that are harmful to your machine and dangerous when inhaled.  

What Material Reflects Lasers?  

Metal gives a unique challenge because they are considered reflective materials. Laser beams will bounce off a shiny surface rather than being absorbed – which could be hazardous for your machine and even your eyes.  

Examples of Reflective Materials:  

• Foil  
• Mirrors  
• Chrome  
• Polished aluminum  
• Stainless steel (uncoated)  

The answer to “What material reflects lasers?” is anything that shines or is metallic. These materials are not ideal for use in diode lasers, except when using high-powered fiber or CO₂ lasers.

What Do Lasers Bounce Off Of?  

Highly reflective surfaces that can “bounce” a laser reflection include:  

• Mirrors used as a backing surface.
• Calibrated metallic boards.
• Softer metal plates.
• White or translucent objects made of ‘soft’ materials.  

Dangerous reflection can also result in optic damage or inaccurate cutting by the laser cutting machine. These surfaces should be treated cautiously and guarded throughout unless the right equipment is used and proper safety protocols are followed.  

What Materials Cannot Be Cut With A Laser?  

Clean cutting (as opposed to melting) on some materials is dangerous due to toxins released or the structure of the material.  

Dangers of Cutting with a Laser:  

Polyvinyl Chloride (PVC) – Guaranteed to release lethal chlorine gas when burned.

Flexible ABS Plastic – Melts, burns, and emits dangerously noxious fumes.

Polycarbonate – Very poor cutting quality, serious discoloration and toxic exhaust.

Post-consumer white MDF – Burning coat reflects light and heat unevenly, coat is inconsistent.

Teflon (PTFE) – Suffers from severe harmful gas emissions.

Fiberglass – Poor melting point, emits harmful vapors.  

If you are wondering “what material cannot be used with a laser cutter,” start with the ones highlighted above. Always remember to consult the MSDS document of the material before proceeding.

Which of the Following Materials Cannot Be Laser Cut?

If you participate in laser cutting or are quizzed about it, know that there is a specific answer to this question. In the event that you are given multiple choices, pay attention to the multiple-choice options such as:

• Reflective
• Contain PVC
• Heat-sensitive materials (foamboard)
• Plastics that are not labeled laser safe

Relevant to the above, the rule of thumb is, if the material emits a strange odor when burned or sticky residue is left behind, it is most definitely a candidate that should not come in contact with lasers.

What Not to Cut with a Diode Laser?

Unlike CO₂ lasers, Diode lasers have different properties and do not work well for cutting clear acrylic or very light-colored materials. Due to their lower power, thicker materials are not possible to work with for these lasers.

Do Not Cut with Diode Lasers:

• Acrylic: white or clear
• MDF: white
• Polished metals
• Vinyl or PVC
• Teflon
• Chlorinated synthetic fabrics

These materials do not absorb the beam effectively, reflect the energy, or release toxic fumes. For optimal results, use dark, non-reflective organic materials.

Can a Diode Laser Cut White MDF?

The answer is no. The chances of cutting through white composite materials are slim because the white surface reflects a large portion of light emitted from the diode laser hindering efficient functioning. Even if this material does eventually cut through, the end result is usually edgy burns, inconsistent depth, unreliable cutting, or fires.

If you really need to cut white MDF, try testing a small area first. You may want to consider dark MDF or raw MDF since they are less energy consuming when it comes to lasers. 

Are Laser Diodes Illegal?

In general, laser diodes themselves are not illegal, but the application makes a difference. 

In most parts of the world, including the UK and the US, the following is true: 

• Use of lasers for personal or hobbyist purposes is permitted. 
• Safety and classification standards must be met for laser products exceeding a certain power level (usually 5mWs).
• It is illegal and dangerous to aim powerful lasers at planes, vehicles, or people.

While it’s true that laser diodes are legal, they have the potential to be abused which can result in fines or criminal charges, depending on the regulations in your area. 

General Tips on Laser Handling Material

• Proper ventilation is important. Always use an active exhaust system or work in a well ventilated area. 
• If you aren’t sure how a material will react, try cutting a small corner outside the design zone. 
• Never leave the machine unsupervised. Materials like wood, paper, or felt can ignite rapidly. 
• Always pay attention to the label on the material. Some parts marketed as “leather” or “wood” may not be genuine.

Conclusions

Undoubtedly, laser cutting is one of the most fulfilling tools in digital fabrication. However, it can be very risky if not done correctly. If you’re using a Flux laser, or any other diode machine, knowing what you can—and cannot—safely cut makes a difference in project quality and overall safety.

To rephrase:

What materials can be laser cut? 

Consider plywood, dark acrylic, natural fabrics, and leather.

What surfaces can cut lasers bounce off? 

Polished metals and mirrors.

What can’t be cut by a diode laser? 

Anything that smells funny when burning, white MDF, PVC, and clear acrylic.

Are laser diodes legal? 

No, not if you’re misusing them.

The same importance is placed on the materials as the machines, and for good reason. Stay within parameters that work and sidestep those that don’t, and you’ll have no trouble designing precise cuts and deep engravings.