When it comes to precision cutting, waterjet and laser cutting are two of the most widely used techniques, each with its own unique advantages and applications. While both methods accomplish the same goal of cutting materials into specific shapes and sizes, they achieve this through very different processes. Understanding the distinctions between waterjet and laser cutting is crucial for selecting the right method for your specific project.

What They Do

Waterjet and laser cutting both excel in precision cutting, but they utilize fundamentally different techniques.

• Waterjet Cutting: This process uses high-pressure water, often combined with abrasives such as garnet or aluminum oxide, to erode material. Think of it as a high-speed, small-scale version of the natural erosion that formed the Grand Canyon. Cutting speeds typically range from 1 to 20 inches per minute, depending on the material and thickness.
• Laser Cutting: A laser cutter employs a highly focused beam of light to heat material to the point where it either melts or vaporizes, skipping the liquid phase entirely. This process allows for incredibly fine and detailed cuts, particularly in thinner materials.

Both methods are versatile and can be used across a wide range of industries, but their effectiveness depends on factors like material type, thickness, and desired precision.

Waste

The waste generated by each method varies significantly:

• Laser Cutting: Thanks to its small beam diameter, laser cutting produces a minimal kerf (the material removed during the process). This enhances precision and reduces waste. However, as material thickness increases, the additional heat introduced can cause unwanted slag (dross), distortion, or burn marks.
• Waterjet Cutting: By contrast, waterjet cutting introduces no heat into the material, eliminating issues like heat distortion or dross in thicker materials. However, it does generate liquid waste (used water) and solid waste (abrasive particles combined with material fragments), which must be managed responsibly.

How Waterjet Cutting Works

Waterjet cutting, also known as waterjet machining, uses high-pressure water to cut through materials. For tougher materials like metal or stone, abrasives are mixed with the water to increase cutting power.

The process works as follows:

1. Water from a reservoir is pumped into an intensifier, which increases the water pressure from around 5 bars to 4,000 bars.
2. This high-pressure water is stored in an accumulator, ready to be released on demand.
3. The water is directed through a nozzle, where it converts to kinetic energy and reaches speeds of up to 1,000 m/s.
4. Abrasives are introduced into a mixing chamber within the nozzle to enhance the cutting power.
5. The high-speed waterjet strikes the material surface, effectively eroding it away to create precise cuts.

How Laser Cutting Works

Laser cutting utilizes a highly focused beam of light to heat material to the point of melting or vaporization.

The process works as follows:

1. A laser source generates a concentrated beam of light.
2. This beam is directed through a series of mirrors and lenses to focus it on a specific point on the material’s surface.
3. The heat generated at the focal point causes the material to melt, vaporize, or burn away, resulting in a clean cut.

Laser cutting is particularly effective for thinner materials (less than ½” in thickness) and excels in speed and precision.

Waterjet vs. Laser Cutting: A Comparison

1. Material Thickness:
   • Waterjet: Ideal for thicker materials and tough substrates, including steel, stone, and composites.
   • Laser: Best for thin materials where precision and smooth edges are critical.
2. Speed and Precision:
   • Laser: Generally faster and more accurate for intricate designs and tight tolerances.
   • Waterjet: While slower, it provides excellent results for thicker or heat-sensitive materials.
3. Surface Finish:
   • Laser: Smoother, cleaner cuts, especially on thin metals.
   • Waterjet: Leaves a slightly rougher finish but avoids heat-related damage.
4. Versatility:
   • Waterjet: Can cut virtually any material, including metals, glass, stone, and composites.
   • Laser: Limited to materials that won’t reflect or absorb too much laser energy, such as metals, plastics, and wood.

Choosing the Right Method

The decision between waterjet and laser cutting depends on the specific needs of your project:

• If your material is thick, heat-sensitive, or particularly hard, waterjet cutting is the better option.
• For thin materials, intricate designs, or high-speed production, laser cutting is the way to go.

Our Response

It’s an age-old question that manufacturing engineers hotly debate in machine shops worldwide. CPT’s answer is “Why not both?” In addition to our state-of-the-art laser cutting, we utilize waterjet cutting to ensure that all your parts are cut to perfection. Waterjet and laser cutting make the perfect machining pair. They play to each other’s strengths and bring unique benefits to the table, so it’s a machine shop’s dream to have access to both. And CPT does make dreams come true! Contact Custom Precision Technologies today at 954-975-5518 or visit our website to learn more about how our waterjet and laser cutting services can take your project to the next level.