How Does Laser Engraving Work?
Way back when, engraving was the method used to start the whole process of decorating as one stone was used to mark another stone. The world's oldest engraving actually dates back 500,000 years ago to a doodle!
Fast forward to 3000 BC, the Sumerian and the Hittite elite began engraving intricate seals in stones and precious gems. Much like today, engraving in the ancient world was used to decorate and design.
In the 1400s the process of engraving became integral to recreating documents and artwork as pieces of wood were carved, the raised portions were coated in paint or ink and pressed into paper or cloth to duplicate an image.
(The Printing Press was essentially a whole bunch of small engravings arranged into sentences and pressed onto pages. Huzzah for Gutenberg!)
Add in a couple of major technological leaps and the invention of the computer...and engraving moved back into the realm of decoration from its major stint as the source of printing.
So what does engraving look like in our modern world? Let's talk about lasers...
Aren't lasers just something from Star Wars?
If you're like me, whenever someone says the word "laser", my first thought is either of the lightsabers in Star Wars or James Bond's Q-built gadget watch.
While those films make lasers look like really cool and dangerous weapons (and some lasers can definitely be dangerous, so be careful), they're more often than not just helpful tools performing a bunch of simple, harmless tasks.
You don't have to be 007 to have a laser; we use them every day!
They're especially good at popping balloons, but you shouldn't try the things you see in this video at home.
Of particular interest to us, however, is a laser's capacity to cut, etch, engrave, or mark various materials—that is to say, its ability to personalize and decorate.
But how do they work?
How do lasers work?
The word "laser" is actually an acronym for "Light Amplification by Stimulated Emission of Radiation."
Verrrrry simplified...light is concentrated over and over again to create a powerful beam. There are three major factors to how this works: Concentration, Energy, and Direction.
Concentration
Light moves in waves—up and down, so to speak.
A normal light has a bunch of different, varying wave lengths (the distance between the peaks of troughs of each wave) which cross over each other.
Now, focus all of the wavelengths so that they don't cross over each other, but instead line up perfectly with each other.
The concentration of light waves cuts out all the extra waves that cross over each other, and it's what makes that cool, mesmerizing beam of (usually) red light. (You can see the whole beam if you crank up a smoke machine; otherwise, it's just that little red dot that cats just NEED to catch.)
This also means that laser light can become extremely powerful and can be focused on a singular point.
Energy
Chris Woodford has a great explanation:
You've probably noticed that if you move your hands back and forth in the bathtub you can make quite strong waves. If you keep moving your hands in step with the waves you make, the waves get bigger and bigger. Imagine doing this a few million times in the open ocean. Before long, you'd have mountainous waves towering over your head! A laser does something similar with light waves. It starts off with weak light and keeps adding more and more energy so the light waves become ever more concentrated.
Give a power source to move those single wave lengths perfectly in time with one another and bam! you have added energy to your concentrated light beam.
Direction
The last major part of laser light is that it is directional. Unlike a flashlight which diffuses white light evenly across a space, laser light creates a tight beam that can travel much farther distances. Breaking out the fancy terms: it is highly collimated (travels parallel instead of zigzagging).
For a more in depth look at the science of lasers, check out this amazing, in-depth video.
Laser light can be invisible to the human eye; a lot of common uses for laser light require light to be invisible instead of burningly bright in order to minimize the risk of what doctors (probably) call "eyeball meltage" or simply "arson."
What are lasers used for?
The unique properties of laser light allow them to perform a whole array of diverse tasks. The FDA has a big list of uses (and cautions) for lasers:
reading disks (Blu-Ray, DVDs, CDs)
measuring distances and speed
reading barcodes
scanning documents in a printer
getting yelled at by your mom for shining it into your brother's eyes (maybe not on the FDA list)
performing complex medical procedures
cutting precious gems
You name it, someone is probably either using a laser to do something or trying to figure out how you can.
You can even make holograms with lasers:
Why are lasers dangerous?
The wavelengths of laser light can be focused on a single point, and if enough energy is added, they can burn almost any material.
The intensity of the light can also damage your eyes if you look directly into it, so using protective glasses is often a must when handling high-powered lasers.
One last safety consideration is the sound made when a laser beam hits an object. Powerful laser beams often emit a high pitched sounds when coming in contact it particularly hard materials such as chrome. Take precautious to wear protective ear coverings when using a laser in this way.
What stops a laser beam?
The easiest and best way is to remove the energy source by either unplugging it, taking out batteries, or switching off the power.
If, for instance, a bad guy has a laser gun pointed at you, grab the nearest mirror to deflect the beam of light away from you. Preferably back onto the mustachioed, dastardly villain.
You can also simply block the laser with another object. If its a high-powered laser, you will want a hard, heavy metal around to do this.
What is a laser engraver?
Laser engraving machines are specifically designed for cutting, etching, marking, and engraving hard materials, automating the process through the use of computer software.
You probably see items engraved on a laser engraver all the time without realizing it. Take a look at just about any plaque on a trophy or the signs on the office doors in your workplace. These are more than likely the product of a laser engraving machine.
There are a bunch of different kinds of laser engraving machines like the Dremel LC40 and the RMI UF-20, and a lot of them have different strengths and weaknesses as far the shape and material of the thing you want engraved.
How do laser engraving machines work?
Now, let's talk about it.
Laser engravers are specifically designed to focus laser light for the purpose of marking wood, metal, glass, or some other material with a preselected engraving—often images or script.
The machine uses lasers to produce concentrated heat that removes the top layer of material, cutting it from an item to create the desired design.
Using powerful lasers and mirrors, the machine reflects a laser beam onto a surface of an object.
The light is focused at the right distance and set to the right power level in order to leave a mark. Too little power and it will not end up cutting into the material, too much and you can burn through the object.
Some lasers (like the GCC Spirit LS machine) are mounted on a track and make passes over the desired engraving area similar to how your ink printer prints on paper. The pro of this kind of laser is you can engrave larger areas.
Others lasers (like the RMI UF-20) are stationary and focus on a smaller surface area. The pro of this laser type is it tends to engrave faster at higher powers.
What is the engraving process on the machines?
Laser engraving machines can have a number of different processes for engraving, but for the most part:
The engraving design is keyed into a computer software like CorelDraw.
The object to be engraved is placed within the laser tray.
The laser engraving machine is then properly focused on the surface of the object.
The power of the laser beam is set depending on the solidity of the material (whether wood, steel, gold, etc.).
The laser operator starts the selected engraving process on the computer.
The machine activates the laser and passes its over the desired marking area on the surface of the object.
The engraving is removed from the machine once it is completed, and engraving residue (soot, metal shards, etc.) is removed from the surface of the object.
Voila!
How long does it take to Laser Engrave?
The easy answer: Laser engraving takes about 3-5 minutes.
The real answer:
Laser Engraving can take anywhere from 5 seconds to multiple hours. Quite a few factors need to be taken into account such as the material being engraved, the size of the design, and the power of the laser to name a few.
Ultimately, if you are having an item laser engraved, it is always best to check with the company doing the engraving to see what their timeline is for engraving.
Though the actual process of engraving may be relatively quick, there may be multiple, longer steps involved in preparing the engraving such as rendering the design into the computer software, prepping the material being engraved, and removing any unwanted residue after the engraving process.
Contact White Dog Engraving
Do you need engraving for your Dallas area business? If so, White Dog Engraving can assist you with all of your engraving needs! To learn more about the services that we can offer you, contact us today by calling (972) 848-7790 or click here.