With the recent release of our new CUT 50 Plasma Cutter System, many customers have been asking what the difference is between plasma cutting versus laser and waterjet. The main reason all three of these cutting solutions come up in conversation is that they all have the capability of cutting ferrous metals such as steel and stainless steel whereas a CNC router is not suited to cut those materials. Adding a plasma solution to the STEPCRAFT product line now gives our customers the ability to cut materials that were not possible before and are not possible on competitors' CNC router systems.
This article is obviously biased towards plasma cutting, but I do want to talk about the advantages and disadvantages of each cutting process because while we are very excited about plasma cutting, there are some drawbacks that are important to know.
How Does Waterjet Cutting Work?
A waterjet cutter is an industrial tool that is capable of cutting a wide range of materials, wider, in fact, than laser and plasma. The process uses a high-pressure water jet or a combination of water and an abrasive, such as garnet, which is sprayed through a ceramic nozzle at very high pressures (usually more than 40,000 PSI). This creates a very fine cutting stream that will wear through any material in its cutting path. The nozzle is moved in the X and Y axes via a gantry system just like a CNC router and is programmed with CAD, CAM, and machine control software.
How Does Laser Cutting Work?
Laser cutting is an advanced process of cutting materials where either a CO2 or Fiber laser driver develops a very powerful focused laser beam that comes to an exact point on the material. This beam eats away at the material leaving behind a very accurate cut with a high-quality finished edge. Compressed gasses can also be used to aid the cutting process. The laser is also moved via a gantry system in the X and Y axes, also controlled by programming from CAD/CAM software.
How Does Plasma Cutting Work?
Plasma cutters use electricity and compressed gas (usually Argon, Nitrogen, or Oxygen) to cut metals. In our case, we use compressed air from a standard air compressor that you can buy inexpensively from a big box store. For the type of cutting you will do with a STEPCRAFT, other gasses are not needed to get quality results. The gas is forced through the nozzle of the cutting torch at high pressure, while at the same time, an electric arc is sent through the nozzle heating the gas (air) to a point where it enters the fourth state of matter known as plasma.
Plasma is extremely hot which melts away the metal as the torch moves through it. The excess metal is blown away by the compressed air in the plasma stream. A water table is used to collect the excess metal, as well as to keep the material cool and minimize smoke from the cutting process.
The torch is moved through the material on the gantry system just like when you are using your STEPCRAFT as a CNC router.
The Advantages and Disadvantages Of Waterjet, Laser, and Plasma Cutting
|Can cut almost anything
|Abrasive materials can be costly
|Cold cutting process is good for heat-sensitive materials
|Produces a lot of noise if not done under water
|No hazardous fumes or waste
|Slow cutting speed for most metals
|Highly accurate cuts
|Very expensive machine and operational costs
|Works even on rough surfaces
|Not suitable for most home workshops
|Can cut a variety of metal and non-metal materials
|Can create microfractures in some materials
|More energy efficient than waterjet
|Still requires 240V or even 480V service to run
|Minimal human involvement
|Compressed gasses that are required are expensive
|Suitable for cutting thin sheets with complex designs
|Can produce toxic fumes
|Faster cutting speed, better suited for production
|Laser cutting machines are very costly
|Not suitable for most home workshops
|Can cut a wide variety of metals
|Produces large heat-affected zones
|Easy to learn and operate
|Less accurate compared to laser and waterjet
|Faster cutting speeds
|Can produce smoke fumes but the water table reduces that
|Can cut through thick materials - up to 5/8" steel
|Bright plasma arc can irritate eyes - special eye protection glasses are always recommended
|Very inexpensive equipment/startup costs (under $2000 for STEPCRAFT M-Series CNC owners)
|Can require some post-processing clean-up work to remove dross (metal slag)
|Inexpensive consumable costs
Waterjet vs Laser vs Plasma Cutting Costs (Purchasing and Operational)
The STEPCRAFT Plasma Cutter System costs $1999.00 and is compatible with any STEPCRAFT M-Series CNC. Note you must have the CNC system (M.1000, M.700, or M.500) for the Plasma to work. The only consumable cost that you need to consider is the torch tip, electrode, and shield. These are very inexpensive, costing under $50 for 10 replacement sets. A torch tip is the most used consumable and this can last you many hours of cutting between replacements.
Compare this to a laser cutting system which can cost from $50,000 for an inexpensive Chinese system to over $350,000 for a high-quality industrial-grade machine. Additionally, you have to figure in the special gasses that are needed and laser cutters have consumable costs as well which can run into tens of thousands of dollars depending on use.
A waterjet cutting system can run you $50,000 to over $200,000 depending on the brand, size, and features. If cutting with an abrasive you have to factor in the high cost of that material as well.
Operational costs for the STEPCRAFT Plasma Cutter will cost between $4-$8 per hour of use whereas a water jet can cost over $30 per hour and a laser can cost over $50 per hour.
Waterjet vs Laser vs Plasma Cutting Quality and Precision
This is one area where laser and waterjet shine over plasma. Waterjet cutters produce the best quality edge finish out of all three machines with a laser coming in second. Even the best laser cutters can produce edge splatter and mild dross depending on the type and thickness of the material being cut. Laser cutters can also produce some heat distortion whereas waterjet is a cold cutting process causing no distortion.
Plasma cutting, due to the high heat of the plasma arc, will cause the most dross (molten metal) on the material from the cutting process. This dross has to be removed after cutting which could be as easy as chipping off with a hammer to sanding off with a grinder and flap disc sander. Dross can be minimized by ensuring you are using the correct feed rate and power settings for your material. This high heat can also cause material distortion, specifically when cutting without a water table. Using a water table significantly reduces the amount of distortion and dross.
Waterjet vs Laser vs Plasma Cutting - What Materials Can It Cut?
The waterjet cutter is the most versatile in this category because the high-pressure water jet stream can cut almost anything - wood, plastic, leather, rubber, and much more. Abrasives are added to cut materials like aluminum, steel, and stainless steel.
Laser cutters can also cut a wide variety of materials but you have the added benefit of being able to cut very complex designs on sheets, boxes, and tubes.
Plasma cutters are not as versatile as laser or waterjet but they do an excellent job cutting metals - both ferrous and non-ferrous. Materials like stainless steel, mild steel, aluminum, brass, and copper can cut effortlessly on a plasma cutter.
This brings me to the biggest advantage of the STEPCRAFT CUT 50 Plasma Cutter System... Versatility! While it is true you can not cut materials like wood, plastics, and rubber with the plasma attachment, keep in mind that the Plasma System is an optional tool that works in conjunction with the STEPCRAFT M-Series CNC system, which itself is one of the most versatile benchtop CNC routers in the world. Because of this, you have even more flexibility than laser or waterjet because you have the whole world of CNC Milling at your fingertips in addition to CNC plasma.
Waterjet vs Laser vs Plasma Cutting Speeds
This is another area where a plasma cutter shines. A typical job on a waterjet can run between 1 and 15 inches per minute, whereas a laser might be closer to 20 to 70 inches per minute. A plasma cutter can cut metals at speeds from 60 to over 200 inches per minute depending on material type and thickness. There is no arguing that plasma is the best solution for high-production metal cutting.
Final Reasons Why The STEPCRAFT Cut 50 Plasma Cutter System Is Better Than Waterjet or Laser
If you were looking for a stand-alone plasma cutting system, there is no doubt that you will spend tens or even hundreds of thousands of dollars less than you would on a Laser or Waterjet. But when you take a look at the STEPCRAFT M-Series line of CNC routers and then consider adding the Cut 50 Plasma System, you are still looking at spending less than the average CNC plasma cutter but you gain all of the additional advantages that come with owning a STEPCRAFT M-Series CNC.
Things like many multi-function tool options allow you to engrave, mill, cut, plot, draw, 3D print, and more. When CNC routing, you have the ability to fit almost any type of project on the machine thanks to the open design of the center of the machine, known as our Freestyle Milling option.
In addition, you also have the capability to add an Automatic Tool Changer to any STEPCRAFT CNC system. There are very few, if any, competitors that offer this feature, nor our other attachments, especially in this price range. Adding Plasma Cutting to our M-Series CNC Systems, amongst our other options, gives you the MOST VERSATILE bench-top CNC System in the world!