Take it from our laser engraving specialists here at Vector & Raster, there is a lot more to the technology and capabilities of laser engraving than meets the eye. Even so, people still tend to be surprised by just how versatile laser engraving technologies can be when it comes to producing engraved or laser cut materials for a wide range of applications. The reason for this is simply that the process of laser engraving isn’t common knowledge.
For instance, did you know that laser engraving isn’t the only technological process that can produce engraved materials? There’s actually a whole other process called ‘CNC engraving’ that can produce engravings of a similar calibre. So why do we need laser engraving? Or better still, what are the differences and similarities between laser engraving and CNC engraving? And how do you know which process is best suited to your engraving project?
We’ll be exploring all the answers to these questions today in order to shed some light on the CNC and laser engraving processes.
What is laser engraving?
Laser engraving is the process of using laser technology to create precise engravings on a range of materials. The laser head is guided by numerical control technology in order to produce engravings that correspond to a digital design.
Laser engraving is also a non-contact production method. This means that laser engraving machines don’t use a physical drill machine head, but instead use a laser source and intense and focused heat in order to alter the surfaces of a material.
Laser engraving machines employ an X-axis and a Y-axis to navigate across the surface of laser engraving materials like cork, plywood, plastic, acrylic, cardboard, fabrics, leather, rubber and silicon, and a range of metals. In addition to this, they also boast a Z-axis to allow for different thicknesses in materials and different sized products. This is likely to be used if you’re engraving onto irregularly shaped or three-dimensional objects rather than surfaces.
What is CNC Engraving?
Before we learn about the technology behind CNC engraving, it’s essential that we explore CNC machining as a concept. In a nutshell, CNC stands for ‘computer numerical control’, and it refers to the automated control of machinery by computers in order to fulfil a desired process.
CNC engraving involves using CNC machinery specifically to create engravings on a variety of different surfaces, ranging from wood to anodised aluminium, and virtually all other materials that can be used for laser engraving, so long as those materials are rigid.
The reason why CNC engraving processes aren’t applicable for less rigid materials like fabrics and rubber, is simply because most CNC engraving machines typically use a milling head with an attached drill bit in order to physically carve into materials. As a result, much like laser engraving, a good extraction system is required, as are safety goggles due to the large amounts of dust and debris that is created by the physical engraving process.
Key differences between laser engraving & CNC engraving
There are some major similarities between laser engraving and CNC engraving, the least of which is that both of these methods can create similar results: neatly and precisely engraved materials that correlate to a provided design plan. On top of this similarity, laser engraving and CNC engraving both use numerical control to facilitate the engraving process. So both methods use computing to read a design and then produce an engraving that aligns with that provided design.
So how do they differ? Alongside their different approaches to the engraving process, CNC engravers and laser engraving machines also look quite different as well. Whilst laser engraving machines generally employ an X-axis and a Y-axis when working with flat materials (unless engraving a 3D design), a CNC engraving machine will always use three axes during processing.
Unlike laser engraving, a CNC engraving machine makes contact with the material being engraved. This means that the machine’s spindle will move up and down to produce your desired depth when engraving as well as clearing the material when adjusting positions during engraving. The direction of this additional dimension is dictated as appearing on a Z-axis by the program control system being used to operate that CNC machinery.
Alongside this functional difference, the end product between a laser engraving and a CNC engraving are also likely to look distinct from one another. As the laser engraved end product has been created using non-contact processes, this creation is less likely to hold superficial flaws. Contrastingly, CNC engraved materials may potentially hold some minute flaws caused by any number of factors, like the material being held in place by a poorly installed jig which would then cause the milling head to move irregularly.
Advantages and disadvantages of laser engraving
As laser engraving machines use a high-power density laser beam directed through an optical path system that makes no physical contact with your work materials, the process of laser engraving is naturally positioned to provide a higher quality end product that’s less likely to bear superficial flaws. This means that laser engraving processes will essentially guarantee that the same end product will be produced time and time again, with little to no discrepancies between two copies of the same digital design.
As laser engraving works by using intense heat on a work material, the process actually produces far less waste in comparison to CNC engraving, which can produce a lot of dust. This is another reason why laser engraved products are likely to boast a smoother finish when compared to items produced using CNC engraving processes.
The one disadvantage to laser engraving could be the fact that a laser can only produce less dust and debris by turning that material directly into fumes over dust. As a result, laser engraving machines require specialised filtration systems to keep these workspaces safe.
Thankfully, this is not an issue for our laser engraving specialists here at Vector & Raster because of our high-efficiency, multi-stage filtration units, designed specifically to combat the fumes and fine dust particles produced during the laser engraving process. On top of this, our studio maintains sustainable laser cutting practices, which ensures that both our engraving machines and our filtration units, all run entirely on renewable energy sources.
Advantages and disadvantages of CNC engraving
Although CNC engraving isn’t as precise in its nature as laser engraving machinery, the CNC engraving process is still able to produce end products of a high calibre. We’ll also be the first to admit that CNC engraving is a fairly satisfying process to watch as well. There’s something a little mesmerising about watching a physical drill bit carve its way through a smooth surface to produce intricate designs by following a numerical control system, all before your eyes.
Of course, because it is a production process that does require milling heads to make contact with your work materials, there is also more space for error when engraving with CNC technologies. CNC engraving technologies can also use more energy than laser engravers because of the amount of torque required for the drill bit to cut through your work material, although this is dependent on the depth and texture of that material.
For this reason, there is a potential for the CNC engraving process to be comparatively wasteful, not only with with regards to the power used to complete the process, but also potentially in the mishandling of a material as well as in the production of dust and debris generated when engraving with a drill bit.
Is laser engraving better than CNC engraving?
It’s no secret that we prefer laser engraving over CNC engraving here at Vector & Raster. After all, we’ve built our whole business and studio space over providing our clients with high-quality laser cutting and engraving services. Even so, our laser engraving specialists do agree that there are certain benefits to using CNC engraving technologies for some particular projects.
For example, if you’re working with sturdy materials and require very deep engraving or if you require depth into metal for paint filling, then a CNC engraving machine that uses a rotating drill bit over a laser source is likely to be the way to go.
If you’re after high-quality engraved products then we’re inclined to recommend the precision and power of laser engraving as the path forward for you.
Want to know more about our laser engraving services and other production capabilities here at Vector & Raster? Explore some of our latest projects to get a taste of what our laser cutting and engraving specialists can do for you.