Cutting accuracy is vital in many industries because it ensures that the cut materials are prepared correctly for the next stages of the production process. Accurate cutting reduces the chance of mistakes and waste and helps ensure the final product is well-made.

Waterjet cutting is a widely used technique in various industries, known for its ability to deliver precise cuts. The accuracy of waterjet cutting is a critical factor in determining the final product’s quality.

In this article, we will explore everything about waterjet cutting accuracy, discussing the factors that can affect it and the benefits of achieving high-precision cuts. Additionally, we will provide valuable tips on how to maximize the accuracy of waterjet cutting.

How Accurate Is Waterjet Cutting?

Waterjet cutting is highly regarded for its exceptional precision. Accuracy is a crucial factor when it comes to reducing tolerance. Cutting tolerance refers to the minor deviation of the final cut from the intended cut. While all cutting techniques experience some level of tolerance, waterjet technology practically eliminates this issue.

In typical waterjet machines, the cutting tolerance is typically 0.002″ (0.05 mm). Some advanced waterjet cutters can even achieve a tolerance as low as 0.001″ (0.025 mm) or less.

This level of precision is so minute that the naked eye cannot perceive it. Even a conventional ruler could not measure such a small scale accurately.

What Factors Affect Waterjet Cutting Accuracy?

Waterjet cutting is a versatile and efficient method used in various industries to cut a wide range of materials with high precision. 

However, achieving the desired accuracy in waterjet cutting depends on several factors. Here are some important factors that affect waterjet cutting accuracy:

The Speed of Cutting

Operating a machine more quickly will result in less accuracy and a larger tolerance. The speed at which the waterjet cutting machine moves can significantly impact the cuts’ accuracy. Slower cutting speeds allow for more precise control, resulting in higher accuracy and smaller tolerances.

Abrasive Quality

The abrasives employed in the cutting operation may affect the waterjet stream’s behavior. There are several acceptable abrasives, but uniformly sized and formed abrasive particles will increase uniformity and accuracy.

These are the basic characteristics of any garnet or waterjet abrasive material. Choosing high-quality abrasives and maintaining their uniformity can improve the accuracy of waterjet cutting.

Workpiece Thickness

A workpiece will be more challenging to cut using a waterjet cutting machine correctly the thicker it is. The waterjet’s cutting precision often drops below 0.1″ for materials thicker than an inch, which is a significant decline. This is partly due to the fact that the waterjet must first drill a hole into the workpiece to cut precisely.

A waterjet cutting machine often produces an initial hole that is slightly atypical. The hole will be more erratic because the first cut requires more effort when the workpiece is thicker. However, the remainder of the cutting line should be precise after it has been cut through. 

Position and Stability

Inadequate waterjet cutting machine placement may sometimes lead to greater tolerance. It is crucial to position the machine precisely, considering elements like the waterjet kerf and offset, for accurate cuts and reduced tolerance.

Additionally, any vibrations in the workpiece brought on by external instability can result in flaws and markings on the portion being cut. These witness markings may lead to a larger tolerance than necessary. Ensuring a stable work environment and minimizing external vibrations can help improve waterjet cutting accuracy.

Machine Operator Experience

The results of the waterjet cutting process vary significantly depending on the machine operator’s level of expertise.

Skilled operators can optimize cutting settings and compensate for material thickness and hardness, resulting in better accuracy and precision.

Software and CNC Controllers for Waterjets

The manufacturer’s software and controls may greatly impact cutting accuracy. Opting for higher caliber controllers and software from a reputed manufacturer can result in lower tolerances. These advanced systems can follow the specified cutting path more precisely, enhancing accuracy.

Condition of Cutter

In comparison to a waterjet cutter with worn-out nozzles or missing pieces, one that is well-maintained will have more precision.

Regular maintenance and utilizing replacement parts as per the manufacturer’s instructions are crucial for achieving the highest level of accuracy in waterjet cutting.

What Are The Benefits Of High Accuracy In Waterjet Cutting?

Waterjet cutters have revolutionized the manufacturing industry with their ability to accurately and precisely cut a wide range of materials. With technological advancements, high accuracy in waterjet cutting has become increasingly important.

The following are the benefits of high precision in waterjet cutting:

Excellent Edge Quality

One of the key benefits of high accuracy in waterjet cutting is the superior edge quality it delivers. Traditional cutting methods often leave behind burns, cracks, or extra burrs, which require additional finishing processes. However, waterjet cutting eliminates these issues by employing a cold-cutting technique.

Since waterjet cutting does not generate heat, no heat-affected zones can alter the material’s molecular makeup, compromising its tensile strength. This results in clean edges free from defects, saving both time and resources.

Cost-Effectiveness

Another significant advantage of high-accuracy waterjet cutting is its cost-effectiveness. Compared to other cutting techniques, waterjet cutting offers lower costs in terms of fixturing and equipment.

Additionally, the process reduces waste material and allows for faster production, resulting in a more cost-effective end product.

Increased Productivity

The efficiency and speed of high-accuracy waterjet cutting contribute to increased productivity. With the ability to operate quickly, 5-axis waterjet cutters can significantly reduce the turnaround time for manufacturing new components.

This enhanced productivity directly translates to shorter production cycles and quicker order fulfilment.

No Heat-Affected Zones

Heat-affected zones can be detrimental to the structural integrity and dimensional stability of materials. However, high-accuracy waterjet cutting ensures that the cutting tips remain cool throughout the process, eliminating heat-affected zones altogether.

The material’s properties remain intact without temperature-induced alterations, preserving its strength and quality. This guarantees that components produced through waterjet cutting maintain their desired characteristics and precision.

The Difference In Accuracy Between Abrasive And Pure Waterjet Cutting

Pure waterjet cutting and abrasive cutting are two different applications of the same technology. In pure waterjet cutting, a material is cut by a water stream.

On the other hand, abrasive waterjet cutting involves using tiny particles called abrasives mixed into the water stream. These abrasives provide cutting power, making them more suitable for tough materials.

Using a pure water stream to cut tougher materials would be time-consuming due to the lack of abrasives. Therefore, it is important to understand the differences between pure water jet and abrasive jet cutting techniques. You can choose the most suitable tool for your job by making an informed decision.

Pure waterjet is appropriate for cutting:

• Foam
• Thin Plastic
• Rubber
• Food products (chicken, cake, or fruit)
• Fabric

Abrasive Water Jet Cutting is appropriate for:

• Aluminum
• Thick Plastics
• Ceramic
• Steel
• Stone

How Does Waterjet Cutting Accuracy Compare To Other Cutting Processes?

For fabricators and machine shops, there are several prominent options for cutting processes, including electrical discharge machining (EDM), laser, plasma, and waterjet. The choice of which technology to use depends on the type of work you perform and the results you want to achieve.

To assist you in making the best choice for your needs, let’s dissect each technology and compare them.

Laser Cutting

Laser cutting is a popular technique that uses laser beams to heat and cut through metal during manufacturing. It is most commonly used for cutting metals like steel and aluminum. Laser cutting is a fast and efficient technique but has some drawbacks.

Unlike waterjet cutting, laser cutting cannot handle thicker materials. It works best for surfaces up to an inch thick. The heat generated by laser cutting can also cause burns or stress scars on the finished product. Laser cutting is limited in terms of material diversity compared to waterjet cutting.

Plasma Cutting

Plasma cutting involves the use of pressurized gas and electricity to create plasma, which can then cut through most materials. Nitrogen, argon, and oxygen are commonly used gases in plasma cutting. Plasma cutting can handle thicker materials than laser cutting and is often used for cutting metals.

However, compared to waterjet cutting, laser cutting is faster and more precise. Plasma cutting is the least expensive of the four cutting techniques. Like laser cutting, it may leave heat-affected patches on the finished product, and a clean edge may require further processing to remove slag or dross.

Electrical Discharge Machining (EDM)

EDM uses electrical discharges to cut through metal. It is a precise process for cutting 12 inches or smaller materials and often requires little to no further finishing.

EDM works only with conductive materials like steel and alloys since it relies on electricity. Depending on the task, multiple wire arrangements may be necessary.

While it may be the slowest of the four methods, EDM can be an excellent option for cutting complex shapes and achieving a specific edge finish.

Waterjet Cutting

Waterjet cutting utilizes high-pressure water streams to cut through various materials, including thick, thin, soft, and hard. It can even produce precisely polished edges. Soft plastics, foam, rubber, and gaskets are easily sliced through by pressurized water at 60,000 psi.

Additionally, abrasive waterjet cutting, which combines pressurized water with sand, can cut through almost any material, including metal and stone. Waterjet cutting is precise and does not induce heat-induced stress or marks on the end product.

It can handle materials up to 12 inches thick for rough cuts and generally does not require further finishing. The cold-cutting technique of water jetting leaves materials with a satin-smooth edge and leaves little kerf behind.

How To Maximize The Accuracy Of Waterjet Cutting?

While waterjet cutting is known for its accuracy, several factors can affect the cuts’ precision. Here is how to maximize the accuracy of waterjet cutting and achieve the best results possible:

Part Thickness

Despite cutting materials with a wide variety of thicknesses, waterjet cutting precision diminishes with thickness. To ensure accuracy when cutting thicker pieces, cutting a test piece first and modifying the program accordingly is recommended.

By fine-tuning the program and using a well-kept and perfectly calibrated waterjet, even extremely thick sections can be accurately cut.

Material

The type of material being cut significantly impacts the precision that can be achieved. Utilizing material with constant hardness throughout and free of internal tension is crucial. 

Materials with inconsistent hardness or internal tension can cause variations in the cut, leading to decreased accuracy. So, choosing the right material and ensuring its quality will help maximize the accuracy of waterjet cutting.

Operator Skill

Having a competent operator is essential when creating components with tight tolerances. The operator must thoroughly understand how to design effective tool paths, maintain stability, and fixture, examine, and change the component to enhance tolerances.

Operators must also be knowledgeable in maintaining and fixing waterjet cutting equipment to guarantee the best accuracy.

Controls

The control system of the waterjet cutting machine plays a crucial role in cutting precision. Machines with more precise controls are capable of making cuts more accurately.

Some waterjet cutting machines come with two axes of angular control at the cutting head, which allows for the highest degree of precision. These waterjets can remove taper from the cut faces, further enhancing the accuracy of waterjet cutting.

Removing taper

Taper refers to the deviation from a perpendicular cut, which can affect the accuracy of component profiles.

The cutting head’s ability to compensate for taper is crucial in achieving reliable component profiles. Also, removing the taper increases the precision of waterjet cutting, resulting in high-quality and accurate cuts.

Preventative Maintenance

Like most machinery and equipment, maintenance is essential to produce high-quality work. Adhering to a consistent maintenance schedule and replacing components at appropriate intervals can ensure high cutting accuracy and precision.

In addition, Regular maintenance will help identify and address any issues that may affect the accuracy of waterjet cutting.

Conclusion

Waterjet cutting is a highly accurate cutting method that offers numerous benefits in terms of precision and efficiency. If you understand the factors that affect waterjet cutting accuracy and follow best practices, you can maximize the accuracy of your cuts and achieve exceptional results.

So, whether you’re in the manufacturing, aerospace, or automotive industry, waterjet cutting can be an invaluable tool for achieving precision cuts. And if you’re interested in investing in one, feel free to browse through our collection or simply contact us.