Incredible facts about laser cutters

Hobarts - Incredible facts about laser cutters

 

We’ve been fans of laser cutting for quite some time, because of the superior results that the process provides. Whether you’re cutting metals, organic material or acrylics, if you’ve got the right type of laser cutter, results are simply better, and much more efficient when compared with manual methods. Although we wrote about getting started with laser cutters a while ago, there is a whole lot more that is well worth knowing – so we thought we’d gather some of those interesting facts together in one place.

 

The history of laser cutting started more than a century ago

Laser cutting started quite a lot earlier than most people think. The connection between energy and the frequency of radiation was first identified as a possibility by Max Planck, with his theory being extended and improved by Albert Einstein in 1905. By 1917, Einstein announced the theory of stimulated emission. Although scientists were aware of the theory, almost 40 years passed before it was possible to prove the theory in a lab. Charles Hard Townes, Herbert J, Zeiger and James P. Gordon finally achieved this in 1945. 

 

Hobarts - The original measurement of laser strength was referred to as ‘gillettes’The original measurement of laser strength was referred to as ‘gillettes’ – a reference to the number of razor blades that a laser beam could cut through. While we like the idea of referring to the power of lasers as gillettes today, most lasers can cut through enough razor blades that the term stops making sense – so it is little wonder that the term was abandoned as lasers grew more powerful.

 

Although the word laser is widely used today, it is actually an acronym that stands for Light Amplification by Stimulated Emission of Radiation. The term was coined by Gordon Gould – who was a Columbia graduate student – in 1959. 

The first carbon dioxide laser was developed in 1963 by Kumar Pael, which provided more power at lower cost compared with ruby laser technology. By 1967, CO2 lasers were being used alongside oxygen jet cutting to be able to cut through sheet steel of just 1mm thick. As technology developed, laser cutting began to be used in manufacturing. In 1970 The Being Company created multi-beam laser cutting technology, which allowed much harder materials such as titanium to be precision cut to create components. 

3D laser cutting was first developed in 1979, and uses a five axes rotation system. Fibre laser cutters only emerged for commercial use since around 2008, but they are becoming one of the most popular types of laser cutter for businesses to invest in.

 

 

There are several types of laser cutters

Today there are several different types of laser cutters on the market, with thousands of individual models available to buy in each category. Not all laser cutters can cut all types of materials though – each type of laser cutter is best suited for cutting certain materials. The three most commonly used types of laser cutters are:

 

Gas lasers 

CO2 lasers create a laser beam by electrically stimulating a carbon dioxide gas mixture. They create a beam with a wavelength of up to 10.6 micrometres, and are used on non-metallic materials and some types of plastics. They’re pretty efficient, and the beam quality is high, so this type of laser cutter are amongst the most commonly used. The downside is that they can’t be used with metal materials. 

Gas laser cutters can be used with: Wood, acrylic, glass, paper, textiles, plastics, some types of foils & films, leather, stone

 

Crystal lasers 

Crystal lasers are also a type of solid state laser. The most common type of crystal lasers are nd:YAG (neodymium-doped yttrium aluminium garnet) and nd:YVO (neodymium-doped yttrium ortho-vanadate) – you can see why they have shorter names!

These types of lasers create a beam that has a wavelength of 1.064 micrometres, the same as fibre lasers, but they can be used with both metal and non-metal materials. The downside to crystal lasers is that the pump diodes have to be replaced after 8,000-15,000 laser hours, and unfortunately they’re expensive to replaces. The crystal also has a much shorter life span than a fibre laser.

Crystal laser cutters can be used with: Metals, coated metals, plastics, and for some ceramics

 

Fibre lasers 

These are a type of solid state laser. The beam is created using a seed laser that is amplified through glass fibres that are supplied with energy through pump diodes. Fibre lasers create a very small focal diameter, so the beam created is up to 100 times greater in intensity than gas lasers of the same power. These types of laser cutters can cut with metals and non-metals, as crystal lasers can, but they have a much longer working life – around 25,000 hours. The beam intensity is much higher than with gas laser cutters, and parts are much less expensive, although fibre lasers rarely require any maintenance. 

Fibre laser cutters can be used with: Metals, coated metals, plastics.

 

Laser cutters can cut a wide range of materials 

Laser cutters can cut a number of materials, with different types of laser cutters being suited to different materials.

  • Metals 
  • Wood 
  • Paper and cardboard 
  • Plastics 
  • Glass (not all laser cutters – and glass tends to be etched, rather than cut. Always use care when cutting glass)
  • Organic materials including stone and leather

 

Laser cutting is incredibly accurate 

Laser measuring is accurate to just over a nanometre – which is a billionth of a metre. That’s because optical lenses are able to focus the laser to just 0.001 of an inch – just 0.03 of a millimetre. The heat generated by the laser is concentrated into this tiny area, which allows for much more precise cuts than manual methods can achieve. 

 

Hobarts - Laser cutting is incredibly accurate

 

These materials should never be cut with laser cutters

Although laser cutters are incredibly versatile and can cut many different types of materials, there are some that should never be cut with lasers. Once you’ve made a significant investment of buying a laser cutter machine, whether for your business or for personal use, you’ll want it to run well and provide as much value for money as possible, and to perform well for you for as long as possible. 

Some materials don’t just cause problems for your laser cutter though – some materials, when cut with a laser can release gases that are pretty toxic to the human body, as well as harming your machine. Avoid cutting these materials to avoid causing damage to yourself, your staff, or your machine.

PVC, vinyl, and artificial leathers – these materials release chlorine gas when cut, which can absolutely ruin your machine. Optics can be affected by the gas, metal parts of the machine can be corroded, and the control system can be damaged. 

 

Hobarts - These materials should never be cut with laser cutters

 

Thick polycarbonate – this material over 1mm doesn’t cut well with a laser, but the real danger is that it is likely to catch fire. It creates long thin trails of soot that will cause damage to your machine.

ABS – this one is a messy one! It doesn’t vaporise, and at best, it melts and leaves mess inside the machine. At worst, it catches fire. But all that is secondary to the fact that it releases hydrogen cyanide when it is cut – which is extremely poisonous and simply isn’t safe to work around. 

HDPE (milk bottle plastic) – another messy material – it catches fire and melts all over the machine. 

Polystyrene foam – another messy material. It catches fire and burns really quickly, and leaves melted deposits on the machine. 

Polypropylene foam – similar to polystyrene, polypropylene catches fire really quickly. Not only that, as it melts, it drips. Those drips continue to burn and they set incredibly hard – basically it will completely ruin your machine. Don’t do it! 

Epoxy – this is going to create a burnt mess that will ruin the inside of your laser cutter, but it will also release poisonous fumes that are going to cause serious issues for personnel.  

Fibreglass – another one that is going to cause problems for you. Fibreglass is made of two materials that don’t cut with lasers – glass and epoxy resin. We’ve just mentioned the poisonous fumes that epoxy will release – so don’t try and cut fibreglass in your laser cutter either. 

Coated carbon fibre – although thin carbon fibre mat can be cut by your laser cutter (albeit with some fraying) it isn’t a good idea when it is coated. In this form, it will release toxic fumes. Definitely not recommended. 

Foodstuffs – while we understand the hilarity in telling your mates that you precision cut their pizza in the laser cutter, stick to your normal pizza cutter. Laser cutters aren’t designed for cutting food, and your team will cut materials that can be toxic in the laser cutter (think wood or acrylic smoke). If you want to cut food using a laser, it is better to have a dedicated laser cutter for food items. 

Materials with sticky glue backing – any type of material that has sticky glue on it spells expensive trouble for your laser cutter. The glue vaporises, which will coat the lens. After the lens has been coated, it will cloud, heat and ultimately crack the lens, meaning it will need to be replaced.

 

Laser cutters don’t just cut

You’ve probably already discovered that laser cutters can do etching – it is just cutting, except that the machine doesn’t cut all the way through. But many laser cutter machines can also do welding too. The ones that can’t are Nd machines – and although these machines are used for just one type of cutting, they are great for tasks where little or no repetition is required. 

 

There are several techniques to cut materials 

Apart from stating the obvious, laser cutters cut with the laser – there are many different methods of laser cutting, and the technique that is selected will depend on the type of material to be cut and the machine that is available. 

 

Vaporization cutting

Vaporisation is where the laser is directed to a point on the material being cut, where it heats the material until it start to boil and creates a small hole, sometimes known as a keyhole. As the hole grows, the material releases gases that help to break down the material around it. 

This method is most commonly used with materials that don’t melt – so, wood, carbon and thermoset plastics. 

 

Melt and blow

Also known as fusion cutting, the melt and blow technique uses pressurised gas to blow material that has been heated by the laser until it is molten out of the cutting area. This helps to reduce the need for raising the temperature of the material further. 

The melt and blow method is normally used for cutting metals.  

 

Thermal stress cracking

Sometimes also known as fracture controlled cutting, thermal stress cutting is a bit different to other types of laser cutting. Brittle metal or other material is treated with a hot, high powered laser in order to make them more likely to crack, and the crack can then be directed wherever it needs to go. The disadvantage of thermal stress cracking is that it can only be used with thin, brittle materials – stronger materials and thick metals can’t be cut this way. 

This technique is used for cutting glass, or other brittle materials that are sensitive to thermal fracture.

 

Reactive cutting

Slightly different to what might be considered laser cutting, reactive cutting is also known as burning stabilized laser gas cutting. It is a bit like oxygen torch cutting, but utilised a laser beam for the ignition source. 

Reactive cutting is generally used to cut carbon steel that is over 1mm thick, or for use on very thick steel plates without using excess laser power.

 

Laser intensity determines the thickness of what can be cut

How thick a material that can be cut by a laser cutter depends on the intensity of the laser. Lower intensity lasers can cut through thinner materials, while higher powered laser cutters will be able to cut through metal bars. 

Lasers tend to be measured by their power – in 1,000 watts, or kilowatts. The total energy emitted by the laser light every second is the power. 

You can determine the intensity of a laser by diving the power by the area over which the laser is distributed. If you want to do the maths, it looks like this: 

 

A 1 kilowatt laser beam distributed over a diameter of 0.1 mm will result in an intensity of approximately 125,000 watts per mm². 

(source

 

If you don’t want to do the maths – well, you can usually find out the intensity of the laser by checking the manual, or searching for the model of the laser cutter online!

 

Focal length of a laser lens determines the quality of a cut

The focal length of a laser lens is essential to know, since it has a huge impact on the quality of the work a laser cutter can produce. Lenses that have a short focal length create small spot sizes and short depth focus, and so the shorter the focal length, the better the quality of the cut. A shorter focal length also results in a shorter cutting time – especially with thin metal sheets. 

For thicker materials, a longer focal length is essential for high quality finishes at better speeds. Short focal length lasers give a beam that is too wide to ensure the material stays molten as it moves through to the other side, and there is too much taper on the edge, creating a lower quality cut. 

 

There are four main gases used in laser cutting

CO2 laser cutters use the gas to cut metals. But assist gases are also important, since they aren’t interchangeable, and provide a different effect when the work has been completed. The type of gas that is chosen depends on the material that is to be cut, and the finish that is required. 

  • Oxygen tends to be used when cutting steel when the edge is going to be oxidised. 
  • Nitrogen is preferred for clean cuts, when indirect labour costs need to be reduced.
  • Compressed air is often used for thin metals such as aluminium and thinner steel.  
  • Very occasionally, argon is also used as an assist gas.

 

There are four main gases used in laser cutting

 

Costs are also important to taken into account. Compressed air may seem inexpensive, but the cost of running the compressor may mount up. You also need to ensure that the air supply is clean and free of water or oil that can damage the laser cutter – otherwise damage can be caused to the focusing lens and impact on the working life of the machine. 

 

Laser cutting is pretty safe – as long as you’re doing it correctly

For those who have never used a laser cutter, using a laser to cut something does sound like it could be dangerous! And used freehand, a laser could cause significant damage to whatever it was pointed at – it is hot concentrated light, after all. But it is for that reason that most laser cutters are fully enclosed systems that don’t allow the laser to operate unless the required safety doors and catches are closed properly, and they are controlled by computers that ensure the laser is pointed exactly where it needs to be. 

Where laser cutters are fully enclosed and interlocked systems, they are usually considered low risk when they are used as they are designed to be. However, if safety features are bypassed, lasers can cause serious injuries to skin and eyes if the beam is exposed. Basically – as long as laser cutters are used properly, accidents are unlikely.  

Of course, it should go without saying that all machinery should be used with care, and using suitable safety equipment and PPE. If you’re cutting materials that could emit dust or sharp swarf, safety glasses and gloves should be used, and hearing protection may be required too, although laser cutting is generally quiet. If an assist gas is being used, keeping the gas stored appropriately is essential to prevent accidents. 

 

Hobarts - Laser cutting is pretty safe – as long as you’re doing it correctly

 

In terms of the environment, laser cutting is pretty safe too. It helps machine operators to use materials efficiently and with less wastage – which, let’s face it, is always better for the environment, but is also better for businesses in terms of cost savings.

In terms of any potentially harmful fumes, they can be contained within a specified system which can be ventilated properly. If you’re using a fume filtration unit, you’re not only protecting your staff from dangerous fumes and dust, you’ll also be protecting the environment. 

 

The strongest laser has huge potential for damage

The strongest laser is as powerful as a hydrogen bomb, and at Osaka University in Japan, a laser was able to produce a beam with a peak power of 2,000 trillion watts (also referred to as two petawatts) for a tiny amount of time - approximately one trillionth of a second, or one picosecond. While this type of laser power is clearly not suitable for cutting wood, metal or plastic (there simply wouldn’t be any material left!) the potential power that physicists can harness today means that each time a new technology is developed, there is even more potential for industry to make use of it.

 

Laser cutters can be a major expense for businesses

The exact answer to how much a laser cutter costs to run depends on the type of machine that is in question. Many commercial laser cutting machines have an efficiency of between 5% and 45%. But as a rule, laser cutters need plenty of power, so businesses that are considering buying one should take that into account. It isn’t just powering the machine that needs to be accounted for either. Fume extraction systems and the PC will add to the purchase price, but also need powering, which will increase the electricity bill. 

 

Hobarts - Laser cutters can be a major expense for businesses

 

In addition to the cost of the electricity, there are consumables to consider – any mirrors, gases, lenses, and diodes – and daily and weekly cleaning. Maintenance costs may be minimal, but they are essential to ensure the smooth running of the machine and keep businesses on track. 

Finally, you’ll also need to take into account any training costs for existing or new employees. This might be a one-time expense, but is one that is essential, to prevent any accidental damage to the machine (such as by using the wrong material in the machine) and to ensure safe operation of the machine.

 

Laser cutters are used in many industries

With so many potential applications, and with the high levels of accuracy that can be achieved, laser cutters are used by many different industries, especially in manufacturing medical parts where accuracy is essential. Across Europe, the laser cutter market is led by:

  1. Automotive industry (for electronic parts, for metal parts and for the cloth for airbags) 
  2. Consumer electronics (for precision-cut, small parts such as microSD cards and circuit boards) 
  3. Defence and aerospace (for electronic parts, metal parts and safety features) 
  4. Other manufacturing needs 

 

Realistically though, laser cutting technology can be used in almost any industry. The medical industry, for example, rely on many laser cut parts, such as for stents and hospital supplies, but also for cutting titanium for use in orthopaedic plates, pins, and rods. Not only is laser cutting great for metal and plastics, but it is also used for surgery on human skin, bones, and organs. One of the most commonly known applications is laser eye surgery, which has been a routine process for several decades now, with the modern LASIK procedure having been in use for 15 years.  

 

The laser cutting machines market is massive

The global laser cutting machines market is growing at an impressive rate of 9.3% year on year, and it is expected to reach a massive $4.9 billion this year, and $5.7 billion by 2022. This is not only due to new demand from increased production in the automotive, consumer electronics, and defence industries, but also due to the life span of machines – they need to be replaced on a pretty regular basis. (actual figures that might be achieved are likely to be vastly impacted by the COVID-19 pandemic). 

The biggest laser cutting machine market worldwide is in the Asia Pacific region, which is linked to the economies of China, India, and Japan. The demand for high quality products and automation to increase the efficiency of operations is also driving the growth of the laser cutting machines market. 

 

Hobarts - The laser cutting machines market is massive

 

We can also divide the market by the types of lasers (CO2 lasers, solid-state lasers and others – fibre lasers and disc lasers) and the processes that are used (flame cutting, fusion cutting and sublimation cutting). Currently, solid-state lasers are expected to have the highest growth rate in the next five years, since they prevent wastage of materials, are highly efficient (in some cases, comparable performance can be achieved from a 2 kilowatt fibre laser and a 4 kilowatt CO2 laser) and can be up to six times less expensive to operate.

 

The biggest laser cutter manufacturers make billions each year

In the medium and high capacity laser market, these are some of the biggest and best-known companies worldwide: 

 

Coherent

Started in California in 1966, Coherent started out creating a 220-volt power outlet. From there, they were able to create the first commercially available laser, and today their products are found in all kinds of industries – from life sciences and medical, to scientific and graphic arts. Their laser cutting solutions are extensive, with the ability to cut not only metals and plastics, but also organic materials, silicon wafers, glass and carbon fibre reinforced polymers. The Coherent annual revenue is over $1.3 billion. 

 

IPG Photonics

First founded in Russia in 1990, IPG Photonics is now based in in Oxford, Massachusetts. In addition to laser cutting technology, IPG Photonics also provide telecom equipment and medical components. Company founder Valentin Gapontsev and the team first proposed the use of fibre laser technology, and has invested heavily into research to secure their position as a world leader in high-power fibre lasers. The annual revenue for IPG Photonics is over $1.2 billion.

 

MKS Newport

Launched over 50 years ago, Newport Corporation now sell a huge range of products, including lasers, optical instruments, isolation systems, vacuum instruments and more. With headquarters in California, Newport has 15 manufacturing locations worldwide and revenue is estimated to be between $1 billion and $5 billion.

 

Mazak

Mazak is a Japanese machine tool building company that has come to dominate the global market. Their European base is in Worcester, and their product catalogue includes multi-tasking, 5-axis, milling, turning, CNC controls and automation, as well as laser cutting machines. In July 2019, the UK arm alone reported pre-tax profits of £9.2 million, which was up from £4.3 million the year before – which proves the increasing popularity for laser cutting technology in the UK. 

 

Bystronic

Founded in 1986 and operating from Niederönz, Switzerland, Bystronic provides laser cutting, bending and automation systems, as well as press brakes and software solutions. Their global revenue in 2019 was over €840 million, and there are sales and service subsidiaries in more than 30 countries. 

 

TRUMPF

Based in Ditzingen, Germany, and with annual revenue of over €3.5 billion, TRUMPF is one of the largest machine tool manufacturers in the world. As part of their laser technology range, they create high-performance CO2 lasers, disk and fibre lasers, direct diode lasers, ultrashort pulse lasers, marking lasers and marking systems. They’ve also been creating 3D printers for metal components since 2015. 

 

Our final thoughts

We already knew just how fantastic laser cutters were, just from how much we use them day to day – and our clients love them too. But by having taken a deep dive into these facts about laser cutters, we love them just a little bit more – and we’re sure you do too! If you’re in the market for a laser cutter for your business, check out our range, and get in touch for a discussion about what you need your laser cutter to do.