CO2 Laser Machines
CO2 laser machines are used for marking a variety of non-metallic materials. They can engrave lines, curves, and text onto any material with precision.
They operate by using an electric discharge to excite molecules of nitrogen in a gas mixture. The photons then bounce back and forth between two mirrors in a tube—one of which is reflective and the other semi-reflective.
A CO2 laser machine uses carbon dioxide to produce a powerful light beam for cutting and engraving a variety of materials. The laser beam is computer controlled, making it easy to use and guaranteeing precision work. It also allows for rapid turnaround on production runs.
The operation of a CO2 laser begins inside the resonator, a cylindrical glass tube filled with carbon dioxide, nitrogen and helium. A strong electric field energizes the nitrogen gas molecules and transfers their energy to the CO2 molecules, which then CO2 Laser Machine attain a higher level of energy. As the electrons in the CO2 molecules fall back into their normal state, they emit photons, which are then focused by a series of mirrors at either end of the resonator tube.
As the laser light passes through each mirror, it reflects off of them, increasing its intensity. The light then passes through a lens and is focused to a precise point where it can cause material to be vaporised.
CO2 lasers have many industrial applications, including marking, where they can add logos and 2D codes to parts and products. They can also be used for laser welding to join two pieces of metal together. Other uses include otolaryngology, where they can be used as a scalpel in surgeries like ear and throat procedures. They operate at a wavelength of 10.6 micrometers, which makes them easier to use than other types of lasers.
A CO2 laser machine’s engraving head uses a combination of mirrors and lenses to focus the laser beam before it cuts or engraves materials placed inside it. The first two mirrors on the gantry reflect the beam downward toward the lens, which uses a convex shape to create an extremely narrow point of energy. This increases the power of the laser beam and improves its accuracy before it reaches your workpiece to etch or cut.
The CO2 laser cutter also uses a compressed air to clean the workpiece from smoke and debris before it engraves or cuts it. This helps to ensure that your workpiece gets the right results and reduces the time it takes for you to finish a project. If you plan on engraving cylindrical objects, a rotary attachment can be used to manipulate your material and guide the laser beam where it needs to go.
For those who want the versatility of a 3-in-1 laser machine that can 3D print, CNC cut and laser engrave, the Snapmaker is the best choice around. Its 155W fiber laser delivers up to three times the cutting speed of traditional metal sheets and can increase your potential profit margins.
The exhaust fan of a CO2 laser machine sucks the fumes produced by the laser and routes them safely away through ducting to an outside exhaust port. For this reason, the exhaust fan needs to be sized for the amount of air being pushed through it (called its CFM). Additionally, the number of bends in the duct will also affect how much pressure it has and how efficiently it operates. It is advisable to keep the number of bends as low as possible to ensure sufficient airflow and pressure.
Unlike diode laser engravers, a CO2 laser machine can cut and engrave a wider range of materials because its 10,640nm wavelength is absorbed by the majority of non-metals. This allows it to create clean, professional-looking cuts on many types of paper, cardboard, leather, plastics and fabrics. However, the quality of the cut made depends on how thick and dense the material is.
Dedicated manufacturing spaces will often have exhaust ducts that lead to multiple ports in different locations throughout the building, while laser users working in a home or small business may need to route the ducting through open windows and doors. A simple do-it-yourself test to see if your system is providing adequate make-up air involves closing all the doors and windows in your laser space and listening for the exhaust fan to change pitch; this is an indication that the fan is not pulling enough replacement air.
As the laser beam exits the CO2 tube it is quite wide and must be focused. This is accomplished with a lens that focuses the beam to an extremely narrow point which increases power and accuracy. The lens is a convex shape and is located behind the third mirror.
Lenses come in different focal lengths and are made of zinc selenium. Each lens has a unique set of properties that will determine how well it works in a particular application. For example, a longer focal CO2 Laser Machine length will produce a smaller focused spot and a deeper penetration depth while a shorter focal length will produce a larger spot and shallower penetration depth.
While a CO2 laser can cut or engrave without the use of a focus lens, the results will not be as precise. The reason is that fundamental laws of physics (bottle necks) dictate that a beam of light cannot be focused to a size smaller than its wavelength.
When a laser passes through the lens, it is heated up by the focused part of the light and this causes a change in refractive index that shortens the focal length. This effect is amplified if the lens has dirt particles on it. This reduces the life of the lens and eventually makes it unusable. This is why it is so important to keep the lens clean.