An important benefit of the water jet is the ability to cut material without interfering with its inherent structure, as there is no heat-affected zone (HAZ). Minimizing the effects of heat allows metals to be cut without harming or changing intrinsic properties. Water jet cutters are also capable of producing intricate cuts in material. With specialized software and 3-D machining heads, complex shapes can be produced.
The width (kerf) of the cut can be adjusted by swapping parts in the nozzle, as well as by changing the type and size of abrasive. Typical abrasive cuts have a width in the range of 0.04 to 0.05 inches, but can be as narrow as 0.02 inches. Non-abrasive cuts are normally 0.007 to 0.013 inches, but can be as small as 0.003 inches, which is approximately the width of a human hair. Small jets permit the application of minute details within a wide range of applications.
Water jets are capable of attaining accuracy down to 0.005 inches and repeatability down to 0.001 inches. Due to its relatively narrow kerf, water jet cutting can reduce the amount of scrap material produced, by allowing uncut parts to be nested more closely together than traditional cutting methods. Water jets use approximately 0.5 to 1 US gallon per minute (depending on the cutting head’s orifice size), and the water can be recycled using a closed-loop system. Waste water is usually clean enough for the filtering and disposal process. The garnet abrasive is a non-toxic material that can be largely recycled for repeated use. Otherwise, it can usually be disposed in a landfill. Water jets also produce fewer airborne dust particles, smoke, fumes, and contaminants, thereby reducing operator exposure to hazardous materials.
Plasma cutting is a process that cuts through electrically conductive materials by means of an accelerated jet of hot plasma. Typical materials cut with a plasma torch include steel, aluminum, brass and copper, although other conductive metals may be cut as well. Plasma cutting is often used in fabrication shops, automotive repair and restoration, industrial construction, and salvage and scrapping operations. Due to the high speed and precision cuts combined with low cost, plasma cutting sees widespread use from large-scale industrial CNC applications down to small hobbyist shops.
Laser cutting is a technology that uses a laser to cut materials, and is typically used for industrial manufacturing applications. Laser cutting works by directing the output of a high-power laser, most commonly through optics. The laser optics and CNC (computer numerical control) are used to direct the material or the laser beam generated. A typical commercial laser for cutting materials would involve a motion control system to follow a CNC or G-code of the pattern to be cut onto the material. The focused laser beam is directed at the material, which then either melts, burns, vaporizes away, or is blown away by a jet of gas, leaving an edge with a high-quality surface finish. Industrial laser cutters are used to cut flat-sheet material as well as structural and piping materials.