Manipulation of material is an important part of the manufacturing industry. This is used to produce parts as well as prototypes that are needed in producing different machines. Part of this manipulation involves cutting different materials using laser cutting machine into useful shapes and prototypes.
Materials like metal, wood, plastic, glass, stone and so on can be cut by various methods. These are then used to create parts and products that are useful for everyday life and living. Metals such as aluminum remain one of the most used materials. There are a variety of techniques or methods that are used for cutting materials and some of these include:
- Water jet
Laser cutting remains one of the best methods to use for cutting materials especially metals. It is fast, cost-effective and it removes the need for machining.
What is Laser Cutting?
This is a type of technology or manufacturing process that is used for cutting materials. It a thermal process that makes use of a laser beam for cutting. It is used in manufacturing applications, small businesses, and schools as well as by hobbyists.
The process works by using the output of a focused high-powered laser beam and Computer Numerical Control (CNC). The beam generated is directed and concentrated on the material. The sheer force of the beam cuts through the workpiece.
The laser follows a G-code or CNC for the pattern that is needed by utilizing a motion control system. This then cuts through the material either by melting, vaporizing, or burning it away. A jet of gas may also be used to blow away the parts of the material to be cut. This leaves the surface of the material with a high-quality finish.
Laser cutting has some advantages over other forms of cutting like plasma. It is more accurate and also makes use of less energy and with recent developments, it can cut through thick materials. It is done through machines called laser cutting machines. You can read more on this here.
What is a Laser Machine?
These machines are tools that are used in designing projects and precision cutting in a wide variety of industries. A laser cutter is used mainly by engineers, artists and designers to cut as well as etch into flat material. The machines emit high-powered thin beams that cleanly cut or etch a particular shape or design on a material.
The beam pierces through the material using the geometries and patterns pre-defined by the designer or engineer. When used for engraving, the beam burns off the top and thus changes the appearance of the workpiece where the engraving was performed.
Types of Lasers
Three types or methods of laser cutting exists. They are explained below.
This type can also be called CO2 laser. It uses a carbon dioxide (CO2) mixture that has been stimulated electrically. It is suitable and mostly used for materials that are non-metal since its wavelength is 10.6 micrometers.
In this type, the laser used is made from neodymium (Nd) and neodymium yttrium-aluminum-garnet (nd: YAG). These are solid-state crystals that allow for high-powered cutting and they can be used for metal and other materials. Crystal cutting is suitable for welding, boring and engraving.
The challenge with this type is that it uses costly pump diodes when there is a need to replace them. This is after using them for around 8000 – 15,000 hours. Crystal also has a shorter life span. It has a wavelength of 1.064 micrometers.
This is done by the use of a fiber laser. These also are a member of the solid-state. The beam is produced using a solid medium called a “seed laser” instead of a liquid or gas. This is then intensified inside a glass fiber as well as pump diodes.
Fiber cutting requires minimal maintenance and comes with a higher rate of productivity plus a reduced consumption of energy. It operates on the same wavelength of 1.064 as crystal lasers.
What is it About The Beam?
The beam is a line of very high magnitude of light that is of one wavelength and color. Depending on the type of laser, the wavelength may be invisible such as in a CO2 laser. This is on the infra-red segment on the light spectrum.
The beam is produced in a resonator and travels through the beam path of the machine. It may then be bounced around in several directions by different mirrors called beam benders before focusing on the plate. Just before this focused beam comes in contact with the plate, it passes by way of a nozzle bore. Flowing through this bore of the nozzle is an inert gas such as nitrogen or oxygen.
The focusing of the laser beam can be achieved by a curved mirror or special lens. This happens within the head of the laser cutter. This beam can only be effective if it is precisely focused so that it brings enough intensity and energy. The shape of the focus and its intensity must be consistent, perfectly circular and must be at the nozzle center.
When it is then focused on a particular point, the density of the heat at the spot will be quite extreme. This is almost synonymous with utilizing a magnifying glass for focusing the ray of the sun on a material. Focusing this way can burn a hole in a material like paper. It is the same with a laser beam as the intensity and focus are what make it cut through a workpiece.
This highly focused density of light quickly heats the material and melts or vaporize it partially or completely. For light steel, the laser’s heat uses oxygen as the inert gas. In the case of materials like aluminum or stainless steel, high pressured nitrogen is typically used.
How Laser Machines Work
Laser cutters are quite handy tools. Machine shops use them on an industrial scale for cutting very large pieces and for prototyping. Hardware companies use them to make cheap and quick prototypes while artists use them to bring their digital designs to life.
Laser cutters are a kind of Computer Numerical Controlled (CNC) machine. This means they are controlled by the aid of a computer. A designer designs something using software meant for the purpose and sends it to the cutter which cuts the design automatically.
The machine using its laser beam cuts into the workpiece as it receives the design. These machines are quick and they can be used to produce parts in just a couple of minutes. The cutting head moves over the plate following the design of the part desired and cutting this design out.
Using a system of capacitive control, the machine maintains the height of the laser cutting head at an accurate distance. This is between the nozzle and the plate that is being worked on. Maintaining this distance is essential. It is what determines the focal point as it relates to the plate’s surface.
The quality of the cut is affected by increasing or lowering this distance. Other variables may affect the cut quality. When all these variables are properly controlled, laser cutting is a reliable and accurate process.
When it comes to laser cutters, the difference between them comes from the type of lasers they have. This is what defines the type as well as the thickness of materials that they can cut. Lasers with a higher power range are often used industrially.
Those with a lower power range are utilized for thinner materials that are potentially flammable such as paper, wood, plastic. These are typically used by designers and artists. You can read more on how these machines work here https://www.instructables.com/Laser-Cutting-Basics/.
Benefits of Laser Cutting
Having seen what laser cutting is about and how a laser cutter works, it is time to see its benefits. The first advantage of using a laser cutter is the precision it uses in producing shapes and needed parts. These tools are very precise and accurate and they can create complex cuts with great details.
This gives you the freedom to express yourself with your designs. The machine cuts your design accurately the way it is without any room for errors. There is also no need for a clean-up after cutting most times as it is typically ready for instant shipment.
The next advantage of these cutters is that they are fully automated. This in turn helps to save time for production. This also means lower wastage of materials leading to lower cost of production. They are simply effective, efficient and fast.
Thirdly, a laser cutter can be used to cut a wide variety of materials from wood to plastics, to metal, etc. This ensures that you are able to meet production requirements.
Fourthly, these machines are capable of engraving and this provides you with more options when developing projects. With this, you can find a perfect solution for your design and production by bringing different dimensions and depth to your projects.
Additionally, it does not require a change of tools during the cutting process for each distinct cut. One setup is adequate for cutting many different shapes on a material with the same degree of thickness. Tiny and intricate cuts are also quite easy to achieve.
Furthermore, the laser cutting process does not cause any damage, distortion, or warping to your material. Although it uses a high density of heat, the actual Heat Affected Zone is very small. This ensures that it does not affect the tolerance of the material.
Although it has plenty of benefits and is used in a lot of industries, laser cutting has its downsides. One of these includes the need for expertise. The machine cannot be operated by just anyone if you want to get the best quality. You will need a specialist operator to do so.
The challenge with this is you have to pay them well and find ways to keep the operator happy. If they are not available for any reason, it means production may suffer. For this reason, you may need to get more than one specialist operator.
Also, the upfront cost of obtaining the machine is higher than comparable cutting techniques that use plasma or water jet. Also, the laser cutting process emits gases therefore; the room in which the machine is located must be well ventilated.
How to Choose the Right Laser Cutter
When acquiring a laser cutter, you must focus on the primary application you would be needing it for. Will you need it more for cutting or engraving? Because the fact that a machine can perform both functions does not mean it can do so very well. Therefore, choose a machine based on its core function which is either cutting or engraving.
Put Technology over Brand
While it is all good to follow brands, this is not the most important metric. Granted a brand may be able to produce a good machine but you should let performance trump this. If the brand you like offers you the performance you want, by all means, stick to them.
If you find another brand that has a higher performance level, it is advisable to go for such. It might not be as popular but if it is effective, then you should consider the brand.
Buy Your Machine from A Trustworthy Supplier
One way of ensuring you get quality products are being careful where you make your purchase from. If for example you want to purchase a laser cutting machine in Canada, it is important that you only look for trusted suppliers in that location. The sellers must be knowledgeable about the product they are selling. They should also provide you help and support when you need it and have replacement kits available.
Laser cutting is one of the several types of cutting techniques available. This is done by machines designed for this purpose. These tools are fast, accurate, cost-effective and help to make cutting easy and neat.
When choosing one, ensure to buy from a reputable supplier. Also, focus on what the core application of the machine is about. Rather than just choosing a brand, ensure that you prioritize performance.