Cutting, engraving and marking paper with a laser

Identify the paper before any operation

Note the supplier reference, basis weight, thickness and available composition information. For multilayer cardboard, self-adhesive paper or film-laminated substrates, also identify the films, inks, adhesives and treatments. Request the technical data sheet and, when available, the safety data sheet (SDS). A cellulose base alone does not provide information on all constituents.

As a precaution, exclude substrates containing PVC, PTFE or other halogenated constituents. For fire-retardant paper, request the exact composition of the treatment: some additives may pose risks when heated. An unknown treatment must therefore not be approved based on a simple appearance test: first have the composition and the substrate’s acceptance for the machine being used confirmed.

Cutting: produce a through-cut outline

A CO2 source can be used to cut paper. The objective is to separate the sheet along a path: a card outline, an openwork pattern or a model component. This does not guarantee compatibility with all cardboard types or identical capability on all equipment.

Keeping the material flat, the work support and extraction all matter during preparation. On your equipment, these must be implemented according to the model’s instructions. Marks on the back, browning of the edges and fragility of small details are criteria to examine on the sample; an uncolored edge is not guaranteed.

Engraving and marking: two distinct objectives

Engraving aims to remove material from the surface, whereas marking primarily aims to produce a legible change in appearance. On a thin substrate, check that the pattern does not unintentionally cut through the sheet and compromise its integrity. A logo or number may be feasible if contrast and readability are validated for the selected paper.

Do not assume the result will be dark: appearance and contrast must be assessed on the exact reference after its composition has been validated. A result obtained on one paper does not predict how a different reference will behave. There is no universal recipe here based solely on reducing power.

Qualify a representative sample

After the material has been validated against its documentation, prepare a sample with the same printing, layers and adhesives as the final part. To choose a NWS LASER solution, define the desired effect and acceptance criteria before testing. Parameters must be defined within the framework specified by the manufacturer of your machine, without transferring settings from another model.

Assess full cutting, the condition of both faces, marking readability and the integrity of engraved areas separately. Keep a record of the material reference, file version and test conditions. Requalify the result if the substrate or its treatment changes. To present your project to NWS Laser, provide this information and the intended use, rather than just the basis weight.

Plan for fumes and fire risk

Laser operations can produce toxic or corrosive fumes depending on the material and require ventilation suited to the manufacturer’s requirements. Fume extraction and air treatment are defined according to the known composition, the machine and the workstation assessment. A filter does not make a prohibited material acceptable.

Never leave the laser running unattended and limit the accumulation of debris. Ensure effective supervision, follow the cleaning and maintenance procedures in the instructions, and keep the intervention equipment specified for the workstation accessible. Use a machine with its covers and interlocks in good condition. Extraction does not eliminate the risk of fire.

Further reading

Sources and documentation

• University of Wisconsin–Madison — Laser Cutter Safety
• Emory University — materials prohibited for laser cutting, document in English
• University of Illinois Urbana-Champaign — safe use of laser cutters, document in English