Buying a fiber laser cutter can be a significant investment. When shopping for one, you should consider your purposes and the features you'll need. You should thoroughly understand the key features of fiber laser cutters and how these affect the tools' performance.
Fiber Laser Power Source
Top fiber laser cutters can reach incredibly high power levels of up to 30 kW, although they're far too expensive for small-scale use. Technologically, the beam delivery system is the limiting factor on metal cutting machines. Cutting heads designed for lower wattages can't perform effectively with ultra-high-power lasers. To help determine what power source best suits your needs, consider the following:
The thickness of the material you're cutting is one of the most important factors determining how much power you'll need. Lower-power metal laser cutters have difficulty processing thicker material. When deciding how much power you need, consider the thickness of the material you'll be cutting most of the time. As a general guideline, you'll need the following:
- For steel 1/4 inch thick or less, at least 1.5 kW
- For steel 3/8 inch thick or less, at least 2 kW
- For steel 1/2 inch thick or less, at least 3 kW
- For steel 1 inch thick or less, 6 kW
Another factor to consider when choosing your power source is how fast you need to cut materials. More power will give you a faster cutting speed. If you're using a fiber laser cutter for hobby work, you can get away with less power. If you use it all day, you'll benefit from a higher-powered machine. OMTech's fiber laser cutting machines are able to cut up to 3333mm/s in speed with up to 2.8G acceleration.
Laser Head Design
The fiber laser cutter head takes the laser beam and transforms it into a cutting surface. The laser beam passes through a nozzle that expresses a compressed gas such as nitrogen or oxygen. The distance between the cutting head and the nozzle, the intensity of the beam, and the speed of the laser beam and cutting head all impact the quality of the cuts.
Focal Lens Length
Focus lenses for your laser cutter come in different sizes to perform different jobs. An inch measurement identifies each lens. This measurement doesn't refer to the size of the lens. Rather, it refers to the focus distance from the material you're cutting. Each lens creates a different spot size on the material you're cutting. Some of the most common sizes and their uses include:
1.5-inch focal length lens
This lens has a short focal length and is best for engraving fine details and thin lines. This lens isn't a good option for thick cutting lines. Its spot size is 0.003 inches.
2-inch focal length lens
A 2-inch focal length lens is also good for fine engraving and thin lines and detail work. Like the smaller 1.5-inch lens, it's not good for cutting thick lines, but it's a good general-purpose lens. Its spot size is 0.004 inches.
2.5-inch focal length lens
This lens is good for cutting up to 1/2 inch of material and engraving thicker lines. Its spot size is 0.005 inches.
5-inch focal length lens
A long-focus lens such as this one is good for cutting into deep areas where you need room to work. It has a large spot size of 0.01 inches, so it's perfect for making big bulky cuts for large items but not exactly ideal for high-precision and detailed metal cutting.
Laser Focusing Systems
A laser that cuts metal is most powerful when it's focused on the smallest area. Focusing is related to the focal length of the lens. A lens with a small focal length will have a tighter focus and a shorter depth. That's why shorter-length lenses are better for fine, detailed work. Lenses with longer focal lengths have a larger focus and a longer depth. Choosing a lens is a matter of balancing the two features.
Beam position and alignment also affect the focal point. This is one reason quality is important when choosing a laser cutter. Cheap laser cutters skimp on quality parts, so you might end up with a laser that doesn't focus well, negatively affecting the quality of your work.
Air Assist Gases
The most common air assist gasses are oxygen, nitrogen, and air. In rare cases, argon may be used. The primary function of air-assist gasses is to eject the heated material that's been cut out by the laser. Some important factors to consider regarding air assist gasses include:
Impurities in the gas can damage your cutting head, so the purity of your gas is critical. Damaged cutting heads are one of the top causes of machines needing repairs. Check the purity of your air assist gas to ensure it's higher than that of standard compression gas cylinders.Oxygen systems
Oxygen systems have the fewest up-front costs. This is the only system suitable for cutting thicker carbon steel, but it can't be used for stainless steel or aluminum. It's more important to control the pressure of oxygen systems. Slight variations in pressure can negatively affect the quality of your cuts.
Nitrogen systems achieve the best-quality cuts and are the best laser cutter for metal. When you're cutting thinner materials, nitrogen cuts faster than oxygen. Nitrogen is more stable than oxygen because it doesn't heat the material. It only ejects the material after it's cut. The only downside is that nitrogen is delivered at higher pressures than oxygen, which results in higher consumption rates.
Compressed air systems
Compressed air gives you the best combination of speed and cost. However, compressed air is limited in cutting thickness for stainless steel and aluminum. Compressed air can cut materials of almost the same thickness as nitrogen, and it can cut thinner materials faster than oxygen. Compressed air systems have the lowest operating costs, although their cut quality isn't equal to nitrogen systems.
A cooling system is connected to the fiber laser cutter to cool the laser source and the cutting head, which can be damaged by high heat. Chillers automate the cooling process by keeping the lasers at an optimum temperature of 22-23 Degrees Celsius. There are two main types of chillers: air chillers and freon chillers. Air chillers can't cool to below room temperature. They may not have automatic monitoring or warning features. Freon chillers can cool to below room temperature. They automatically maintain the correct temperature and can let your laser cutter run for up to 24 hours nonstop. When using a fiber cutter water chiller, be mindful that you'd have to change your water every 2 months for proper machine maintenance.
Computer Control Systems
Your laser control system is an essential feature of your work's success. The control system controls the head position, nesting, power dimensions, and precision for the cut. Without a high-quality controller, you won't get the intricate and detailed results you want. Look for a controller compatible with various software systems with a high-tech screen that offers precise detail, such as the Cloudray Friendess BCS100 controller used for OMTech Fiber Cutting machines.
Software & Cutting Files
Laser cutting software is used to program the fiber laser metal cutter. A good software will control all aspects of the laser cutting operation with ease, this increases your productivity and makes operating the laser cutter much easier. Cypcut is one of the best laser cutting software options available for sheet metal cutting. For higher-powered cuts above 6kW, we'd recommend shifting to Hypcut software. For tube cutting purposes, we'd recommend using CypTube or TubePro as the software to carry out your fabrication needs. A decent laser cutting software must have an intuitive user interface that grants you full control over the operation process.
Besides that, you must modify and upload your laser cut files to either LXD OR DXF files in order to use the laser cutting software system for metal cutting. This is to ensure a smooth cutting process with all your metal fabrication dimensions fulfilled.
Fiber laser cutters generate a lot of dust and fumes that are dangerous to breathe. The material that is cut away is blown out of the way and needs to be disposed of. Proper ventilation and dust collection are important to the safety of the laser cutter operator. Exhaust systems that use filters remove the particles from the air and either vent the air outside or send it to the location of your choice. OMTech offers a 4-Core Dust Collector with a 5.5kW fan, a 6-Core Dust Collector with a 7.5kW fan, and a 9-Core Dust Collector with an 11kW fan power for different laser power machine ranges and cutting requirements. Speak with an OMTech representative now to figure out the right dust collection fan for your metal cutting needs.
Although fiber laser cutters are generally safe, they pose hazards that should be addressed in the design of a quality laser cutter. These include:
- Laser-generated air contaminants
- Filtration and ventilation requirements
- Fire hazards
A good fiber laser cutter will address each of these possible hazards.
In order for Fiber Cutter machines to function, you would need an electrical transformer connected to your metal cutting machines. Most fiber cutting machines are manufactured in China; hence, the connectivity and power supply will need to be readjusted to fit the power outlets of your operating region. A transformer is necessary to change the power output from 220V to 380V in most common cases. Other power outlets with electrical powers of 208V or 408V will also work with your fiber cutting machines with the help of your transformers. All OMTech machines have an electrical cabinet with fuses connected to the transformer to ensure maximum safety during laser operations.
Sizes, Styles, and Housing
Fiber laser cutters are available in a variety of sizes and styles. Choosing the best option for you will depend on your use case. The workbed will determine the size of the material that you can cut. Another factor that will help determine what type of laser cutter you should buy is the type of material you'll be cutting. Fiber laser cutters work best on acrylics, brick, granite, marble, aluminum, gold, stainless steel, and other metals. They aren't optimal for wood because the wood will eventually catch fire due to the high heat.
Fiber laser cutters can have closed cabinets or open workbeds. Open machines, sometimes called flatbeds, may be a safety hazard in some cases. You may need to purchase additional safety equipment. Fiber laser cutters that are enclosed avoid these hazards.
Next Steps With OMTech's Fiber Laser Cutters
Buying a fiber laser cutter can seem overwhelming when you consider all of the features you need to look for and the possible expenses. You may be tempted to buy the cheapest machine available, but the quality of your fiber laser cutter will greatly affect your finished product. It's worth the extra time to find a high-quality machine. For help with all of your fiber laser cutter needs, reach out to OMTech today.