Laser Cutting and Engraving: Difference Insight

Both laser cutting and engraving machines utilize laser energy to melt materials and shape them into desired forms. While their functions may seem similar and are often confused, they each serve distinct purposes. Understanding these differences can greatly enhance your project outcomes.

Laser cutting and laser engraving are two distinct processes that utilize laser machines, both of which fall under the umbrella of laser marking methods. Because they share this category, it’s easy to confuse the two. This article aims to explore the differences and similarities between laser cutting and engraving.

What is Laser Engraving?

Laser engraving is a precision marking technique that uses a focused laser beam to vaporize the surface of a workpiece, creating a permanent design. A laser engraver, which is a type of laser marking machine, generates the laser beam and leaves a lasting mark on the material.

As a core process in laser marking, laser engraving stands alongside techniques like etching, annealing, and ablation. These methods share similarities in precision, durability, and versatility across different materials, but laser engraving excels in producing deeper, more durable, and highly contrasted marks.

Laser engraving creates marks that are typically deeper than those from other laser marking methods. The depth varies depending on the material and the laser engraver’s settings. The strong contrast between the marked and unmarked areas makes the engraving highly visible, though it might not be as pronounced as in laser etching.

Industries use laser engraving widely for product traceability, identification, and decoration. It effectively marks logos, barcodes, serial numbers, and QR codes on various parts and products.

Laser cutting is a thermal separation process. During the process, predetermined geometries are traversed and cut by the laser beam. As with engraving, a wide variety of materials can be used. A vector-based file (lines and curves of a geometry) is the basis for the cutting process.

This process is used to cut shapes (such as letters, signs and tags) as well as applications that have previously been engraved.

History of Laser Engraving

Its history cannot begin without talking about manual engraving. Before the advent of laser engraved parts, manual engraving was the only way to mark a product. Manually engraving a part involves using a sharp object (engraving tool) to inscribe the marking.

As far back as 500,000 years ago, stone was the most common engraving tool. However, recently, styluses made using metal parts have become common. Manual engraving even evolved over the years due to technological advancement leading to industrialization seen in dot peening and roll marking; however, the reliance on laser technology premised on Albert Einstein’s idea of LASER in 1916, and its optimization in the 1950s led to an industrial wide acceptance of laser marking over the former.

Theodore Maiman created the first optical laser, and Gordon Gould made the original laser light. Lasers later became an important part of drilling when Western Electrics made the first laser machine in 1965. However, its real use in engraving would not be until the advent of CO2 lasers in 1967. Advancements in technology later led to engraving machines like the UV and MOPA laser.

How Does Laser Engraving Work?

With an idea in mind and the steps highlighted below, you have all it takes to laser engrave a part:

Designing

Designing is the first step, and it involves creating a digital representation of the desired pattern, text, or image using graphic design software like Adobe Illustrators, Inkscape, and Onshape.

Afterward, the design is converted into a format compatible with the engraving machine. There are two common formats: Vector and Raster-based, each suitable for different design size, type, and complexity. Vector-based designs are especially popular because they allow the laser to follow precise paths, enhancing accuracy.

Material Preparation

Choose a material compatible with the laser engraver that complements your design. Generally, laser engravers can work on stone, glass, plastics, and metals. However, the types of engraving machines are suitable for a secluded list of materials.

For example, UV laser engravers (cold lasers) do not produce high heat, which limits them to plastics and thermosensitive materials. In contrast, CO2 laser markers are compatible with organic materials.

Laser Configuration

Configuring the laser involves adjusting the engraving parameters based on the material, desired marking depth, and quality requirements. This step is crucial as it directly impacts the final quality of the engraved part.

Key parameters to configure before engraving a part include laser power, speed, and frequency. Here is a short explanation for each parameter:

• Laser Power: This controls the beam intensity. Higher laser power creates deeper engravings, while lower power suits delicate work or thermosensitive parts.
• Speed: This determines how fast the laser head moves across the material. Slower speeds allow for deeper and more detailed engravings, while faster speeds are suitable for lighter markings.
• Frequency: This refers to the number of laser pulses per second. Higher frequencies are used for softer materials, whereas lower frequencies are better for harder materials.
• Adjust the laser focal point for correct alignment with the workpiece surface for sharp and precise engraving.

Engraving Process

The engraving laser machine uses the design instruction from the CAD model to direct the laser beam, which vaporizes the workpiece surface layer and creates the engraved pattern.

The precision of the engraved mark depends on the machine’s settings, while the ease of engraving depends on the machine’s type and sophistication. Sophisticated laser machines have advanced features like automation to ensure consistent and quality results.

There are two types of laser engravers: benchtop and portable. Benchtop engravers are stationary and are suitable for tasks requiring stability and accuracy. In contrast, portable ones are flexible and useful for on-site work and handling large or irregularly shaped parts.

Inspection

The final product is inspected once the engraving process ends to ensure it meets the desired specifications. Inspection includes checking the design accuracy, marking depth and clarity, and the overall quality of the finish. Any discrepancies are addressed by adjusting the laser settings and re-engraving if necessary.

Is Laser Engraving the Same as Laser Cutting?

No, they are different. The engraving process uses a laser beam to remove material from the surface of an object, vaporizing or melting it to create a permanent mark. Hence, its application in product personalization and customization.

In contrast, laser cutting involves using a laser beam to cut entirely through a material. The laser cut the workpiece by melting, burning, or vaporizing it to produce clean, precise edges. It is a sheet metal fabrication technique commonly employed to cut materials like plastic, wood, fabric, and metal parts.

How Does Laser Cutting Work?

Laser cutting uses a high-power laser which is directed through optics and computer numerical control (CNC) to direct the beam or material. Typically, the process uses a motion control system to follow a CNC or G-code of the pattern that is to be cut onto the material. The focused laser beam burns, melts, vaporises or is blown away by a jet of gas to leave a high-quality surface finished edge.

The laser beam is created by the stimulation of lasing materials through electrical discharges or lamps inside a closed container. The lasing material is amplified by being reflected internally via a partial mirror until its energy is enough for it to escape as a stream of coherent monochromatic light. This light is focused at the work area by mirrors or fibre optics that direct the beam through a lens which intensifies it.

At its narrowest point, a laser beam is typically under 0.0125 inches (0.32 mm) in diameter, but kerf widths as small as 0.004 inches (0.10mm) are possible depending on material thickness.  

Where the laser cutting process needs to start anywhere other than the edge of the material, a piercing process is used, whereby a high power pulsed laser makes a hole in the material, for example taking 5-15 seconds to burn through a 0.5-inch-thick (13 mm) stainless steel sheet.

Differences Between Laser Cutting and Engraving

Both processes are categorized under the laser marking procedure. This is because they use laser marking machines to generate beams that can vaporize part or all of a product. Although similar, below are some differences between laser cutting and laser engraving:

Principle of Cutting

Laser cutting involves using a laser beam to cut through the entire thickness of the material by melting, burning, and vaporizing. Most cuts are perfect. Hence, they don’t need a second touch-up. On the other hand, laser engraving involves cutting to the desired depth without cutting through the entire thickness. Therefore, engraved materials only have their surfaces vaporized to the required depths.

Laser Power

One of the most important disparities in the laser cutting vs. laser engraving process is based on the machines used. Here, the laser power is a definitive parameter. On the one hand, laser cutters are machines with a laser power above 60W. High power is important for cutting, although it depends on the material’s type and thickness. On the other hand, laser engravers have a laser power below 60W.

The difference in laser power also restricts the types of laser machines compatible with the process. For example, most laser cutting machines are fiber or CO2 laser markers. However, laser engravers can include other laser marking machines, such as UV or green lasers.

Keynote: Laser engravers can cut thin sheets of non-metals.

Lens Focal Length                                             

Another important difference in comparing the two processes is the focus lens used in the laser machines. Laser cutting machines have a lens with a long focal length. Consequently, they deliver smooth cut edges, making them aesthetically pleasing. On the other hand, laser engraving machines have a lens with a short focal length. Consequently, they give an object a finer spot size, improving the engraving quality.

Cutting Speed

Generally, the laser cutting process is very slow due to the time and energy it takes to completely vaporize a material. However, this depends on the material you are cutting and its dimension. For example, a thin metal will take less time than a thick one, while a thin plastic will take less time than a thin metal. Furthermore, the slow cutting speed ensures that the forefront is smooth and of good quality.

Laser engraving has a higher cutting speed as the process does not involve cutting. Aside from that, it aids efficiency and reduction of contact time. However, cutting at too much speed can lead to low-quality marking.

Design File Format

Laser cutting machines use vector design files, while engraving machines use vector and raster design files.

The vector design format is applicable in laser workings that require thin lines, and it involves using laser beams to trace the lines and curves of the design vector by vector. Vector design files can be in EPS, AI, or CDR formats.

The raster design format applies to laser working materials such as wood, stamps, and papers. It involves building the design from pixels and engraving it line by line or point by point. Raster files are in JPG or PNG format.

Use of Assist Gas

Assist gases such as helium and oxygen helps in expelling the molten material seen during the laser cutting process. As a result, they are highly recommended for cutting thick materials. Aside from expelling molten materials, they also cut a smooth finish look.

On the other hand, laser engraving does not require to assist gas because it can create a pop that affects the outlook of the surface finish. However, you can use it when the engraving process produces too much smoke, as the gases prevent the smoke from affecting the marking quality.

What Does Laser Cutting and Engraving Cost

What does laser cutting and engraving cost?’ This is a question that lots of customers ask, but it’s a lot like asking ‘How long is a piece of string?’

Each piece of work is different. Commissions are produced from different materials of different thicknesses in different quantities, so there are lots of variables. Here are the main ones to consider to make sure the right product is created for customers at the right price and the right quality.

Artwork set up fee

My standard artwork set up fee is £45, but this can be more if the artwork if complex and significant in volume. It’s a one off unless the artwork changes and it covers 2 to 3 iterations incase the it’s not right first time.

Production time

Production time for laser cutting and engraving costs £1 per minute. A job that takes 30 minutes will cost £30 + materials + artwork set up. If it takes a hour, production time would be £60.

For larger jobs, there can be a discount depending on the intensity and complexity of the job.

Quantities required

Small production runs are more time consuming and therefore less economical than longer runs, especially if lots of fine tuning is needed to get the results right. Customers rightly expect that a run of 10 small pieces is going to cost much more than a run of 100+. It’s always worth making prototypes before ordering a larger quantity to make sure you’re happy with your product.

Price of materials

Different materials cost different amounts.

Mdf is a bit cheaper than laser ply at the same thickness. They’re some of the best value materials I work with and are much cheaper than perspex at the same thickness.

Bespoke pieces of wood for signs will depend on the wood required and the size required. Fabric, card, formica, mylar and other materials can all be sourced at different sheet sizes from different suppliers depending on the colour and quantity required. Some suppliers only sell large sheet sizes, while some will sell a restricted colour range depending on what their core customers require.

Laser Cutting vs Laser Engraving for Metal

Application for Different Materials:

In general, laser cutting machines have higher power, often equipped with CO2 and fiber laser sources, allowing them to process a wider range of materials.

Fiber laser cutting machine is suitable for thicker materials, including metals, alloys, plastics, and organic glass. It is particularly well-suited for precise and rapid cutting of metal materials.

Metal materials include stainless steel, aluminum, copper, iron, etc. Non-metal materials include PVC, acrylic, density board, wood, etc. Materials that can be processed by laser cutting include metals, acrylic, density board, wood, etc. In comparison, laser engraving machines can handle thinner portions of metals, alloys, acrylic, density board, wood, KT board, and similar materials.

Difference between Laser Engraver and Laser Cutter

Laser Cutting:

Purpose:

Primarily used for precise shaping and cutting through metal materials to create accurate components.

Process:

The laser beam is focused on the metal surface, and under the high-temperature action of the laser, the metal evaporates or melts, achieving precise and clear cutting along a predetermined path.

Applications:

Widely used in manufacturing, automotive, aerospace, and metal fabrication industries for producing complex metal components, parts, and prototypes. Applicable to various materials, including metals, plastics, wood, etc.

Laser Engraving:

Purpose:

Generally used for non-metal materials such as wood, leather, paper products, and plastics. It can also engrave some metal surfaces with suitable coatings.

Fine Engraving:

Laser engraving can achieve very detailed engraving effects, suitable for applications with high requirements for patterns, text, etc.

Flexibility:

Different effects can be achieved by adjusting the laser’s intensity and engraving depth, providing high flexibility.

Non-contact:

Similar to laser cutting, laser engraving is a non-contact processing method that does not damage the surface of the workpiece.

Applicable to Various Materials:

Laser engraving can be used for various materials, including wood, plastics, glass, etc.

Material Removal: Laser cutting forms shapes by cutting through the material, while laser engraving forms markings by removing surface material.

Purpose: Cutting is used for manufacturing components, while engraving is used for decoration and identification.

Depth: Cutting is typically deeper, while engraving is surface treatment.

Applications: Laser cutting is primarily applied to achieve functional parts, while laser engraving focuses more on aesthetics and identification. In the case of metal materials, laser cutting is commonly used in the manufacturing sector, while laser engraving is more suitable for identification and decoration purposes.

Laser Cutting vs Laser Engraving for Woodworking

Using CNC laser cutting and engraving on wood depends on factors such as the type of wood, hardness, and other parameters like humidity or texture. The more uniform the color and texture of the wood, the better and more uniform the laser engraving effect.

During laser cutting, the laser beam passes through the wood, rapidly evaporating excess debris to ensure clear and clean cutting edges. CNC laser cutting is well-suited for woodcraft projects requiring high precision and detail, such as puzzles, decorations, or architectural models.

For laser engraving, consistent engraving can produce patterns with specific depths, resulting in subtle transitions and gradient colors. By adjusting the engraving depth, different levels of engraving effects can be achieved, ranging from shallow to deep, meeting various design requirements. Deep engraving is often used in the creation of wooden artworks, signs, or personalized gifts.

Adjusting the intensity and engraving depth of the laser can yield different effects, making the engraving process more flexible. This allows for the creation of more three-dimensional and rich effects on the wood surface. Additionally, by controlling the laser’s movement path and intensity, different depths and details of engraving can be achieved to meet specific design needs.

Can I Use Laser Cutting Machine for Engraving?

Yes, laser cutter are generally capable of engraving. Laser cutting machines use a high-energy laser beam to cut or vaporize materials, and this technology can create patterns, text, or designs on different types of materials. In some cases, by adjusting parameters, using appropriate lenses, and adjusting focus, simple engraving effects can be achieved.

Laser cutting system are primarily designed for cutting materials rather than engraving. Laser engraving machines are specialized for creating patterns, text, or designs on the surface of materials. For dedicated engraving tasks, it is usually recommended to use a laser engraving machine specifically designed for that purpose.

Application Areas:

Laser cutting has a wide range of applications, including but not limited to the metal industry, automotive manufacturing, electronics manufacturing, aerospace, and more. In these fields, laser cutting can be used to cut metal plates, tubes, parts, etc., with the advantages of high precision, speed and low cost. Laser cutting is usually faster than laser engraving.

Laser engraving also has a wide range of applications and is mainly used in the fields of art, handicrafts, gifts, signs, and decorative materials and so on. In these fields, laser engraving can be used to produce various patterns, text, images, etc., with the advantages of high precision, good effect, fast speed and so on. In addition, laser engraving can also be used in the fields of container printing, leather texture processing, wood product engraving, etc., which can improve production efficiency and reduce costs.

Advantages & Disadvantages: Laser Cutting vs Laser Engraving

Conclusion

In the modern landscape of manufacturing and design, the advent of laser technology has unlocked new opportunities for creators and manufacturers. In this article, we will thoroughly compare the differences between laser cutting and engraving, examining their unique characteristics and suitable applications. Whether you need precise cutting or deep engraving, our analysis aims to help you make informed decisions and fully leverage the potential of laser technology in your projects.

Both laser cutting and engraving machines utilize laser energy to melt materials and shape them into desired forms. While their functions may seem similar and are often confused, they each serve distinct purposes. Understanding these differences can greatly enhance your project outcomes.