CNC Waterjet cutting is a specialised manufacturing process that uses a high-pressure jet of water to cut or shape various types of materials. The power of the CNC waterjet cutting machine comes from a pressurising pump that uses a small precision nozzle. As the water exits the nozzle, it delivers a supersonic stream of water, about three times the speed of sound.

What Materials Can A CNC Waterjet Cutting Machine Shape?

CNC waterjet cutting machines using water as a medium can cut or shape softer materials such as wood, different types of plastics and rubber. If you are cutting a stronger material like titanium, stainless steel, aluminium, glass, ceramics and concrete, you can add an abrasive to the water stream. This makes the cutting more aggressive and capable of shaping or processing much harder metals.

This versatility is hugely beneficial for companies that provide a wide range of services to several sectors requiring different materials for different applications. A CNC waterjet cutting machine can ensure that all parts are identical in terms of volume while producing minimal waste. Let’s take a closer look at how the process works, the main benefits and the different applications.

How Does A Water Jet Cutter Work?

Many people refer to a CNC waterjet cutting machine as a tool that accelerates “erosion”. The reason is quite simple since it’s more of a non-thermal mechanical sawing process synonymous with a bandsaw to cut materials. As mentioned earlier, the nozzle pushes a thin stream of high-pressure water to shape or cut the chosen material.

Typically, the nozzle connects to a high-pressure water pump that supplies the machine with the required pressure. The supersonic stream of water is directed through a small jewelled opening to create a highly efficient and extremely powerful cutting tool. You can also integrate the nozzle into multi-axis motion equipment such as a 5-axis waterjet.

Here, the cutting head is often mounted to a robotic arm which can cut bezels and contours by controlling the angle of the cut. Of course, you can use the traditional method of angle grinding but a CNC waterjet cutting machine is much quieter and more accurate.

What Is Abrasive Waterjet Cutting?

As we’ve established, there are water-only cutting and abrasive waterjet cutting. Water-only machines use clean water and can cut soft materials like polymers whilst abrasive waterjet machines use water mixed with an abrasive to cut harder materials.

Mixing the abrasive into the stream occurs inside the waterjet cutting head where the high-velocity water stream creates a vacuum. This essentially sucks a measured amount of abrasive into a mixing chamber to produce a powerful jet stream.

When you add the abrasive, the jet stream now has abrasive particles which exit the focused tube that can wear through harder materials. A CNC waterjet cutting machine can cut many materials, even granite, but one that it can’t is tempered glass which will shatter.

What Can You Make Using A Waterjet Cutter?

Water jet cutting is used to create a near-limitless number of items, including components, materials, and parts for various sectors. It is utilised in a wide range of applications, from high-precision components for aerospace to decorative ornaments for your home. Below is a list containing a few examples of items that have been produced using CNC waterjet cutting.

  • Wooden electric guitar
  • Steel or aluminium gears
  • Sinusoidal Cam for an Internal Combustion Engine (ICE)
  • Chains
  • Nameplates
  • Cut granite, marble, porcelain, neolith, ceramics, stone and tiles
  • Insulation materials such as HVAC liners and PU rubber

Benefits Of Waterjet Cutting

Whilst there are many methods for cutting, shaping, and forming, all of them have one significant disadvantage and that is heat. Waterjet cutting is different as the item in question remains cool with no Heat-affected Zones (HAZ) while being cut accurately and to spec.

It’s considered a cold process where the molecular structure of the component stays the same without any thermal stress occurring. Below is a list of the main advantages of using a CNC waterjet cutting machine.

  • No fibre pull-out and no mechanical stresses
  • Lower cost of operating and easy to use
  • Extremely detailed geometry
  • Versatility in cutting thin or thick materials
  • Stack cutting
  • Low material loss
  • Little to no burr
  • When using a 3D Dynamic Cutting Head, machines can cut chamfers, tapers and intricate geometry which was not possible in the past.
  • Dynamic cutting ability automatically compensates for taper and jet lag in cut parts
  • Environmentally safe

Disadvantages Of CNC Waterjet Cutters

CNC waterjet cutting machines are often more expensive and require a larger initial investment than their manual counterparts. However, this technology has become more common which means costs have already started dropping compared to a few years ago.

Cutting time is usually longer than traditional machines which mean less output. Some low-quality waterjet nozzles can break down and disrupt cutting, which could impact delivery time and productivity. The thicker the component to cut, the less accurate the machine as the nozzle is further from its point of impact. In some cases, the jet can spread and create diagonal cuts instead of straight up and down.

Unemployment is always a big talking point when it comes to any form of automation and technology. The good news is that although CNC waterjet cutting machines require fewer people to operate, there is a growing demand for software engineers and mechanical engineers.

CNC Waterjet Cutting At PRV Engineering

The application of CNC waterjet cutting is so versatile that virtually every industry across the world uses this technique in one way or another. It is by far the superior choice compared to any other cutting method which makes it ideal for several industrial operations regardless of scale.

At PRV Engineering, we use hydro-abrasive waterjet cutters that can process nearly any material quickly and with extreme precision. Our state-of-the-art machining centres can cut various materials into any shape or size from basic mild steels to the more exotic Monel, Inconel, Hastelloy and Titanium.

To ensure only the best quality fabrication services, PRV Engineering has invested in cutting edge CNC waterjet cutting machines and expertly trained, highly qualified staff. If you need help with a project, no matter the size, or would like more information on our services, please contact us today.