CNC waterjet cutting is often considered when a part is too thick, too heat-sensitive, or too difficult to cut cleanly with thermal cutting processes. It may look like a simple cutting method, but the right decision depends on material type, thickness, tolerance needs, edge quality, and whether the part still requires secondary CNC machining.
In this guide, we explain how CNC waterjet cutting works, where it performs well, and when another process may be more suitable. A clear understanding of these factors can help you avoid unnecessary costs, prevent design issues, and choose a more practical manufacturing route for custom parts.
What Is CNC Waterjet Cutting?
CNC waterjet cutting is a cold cutting process that uses a high-pressure stream of water to cut material along a programmed path. The CNC system controls the cutting head based on digital toolpaths, so the machine can cut flat profiles, internal openings, and complex 2D shapes with consistent movement.
CNC waterjet cutting is usually divided into pure waterjet cutting and abrasive waterjet cutting. Pure waterjet cutting relies only on high-pressure water, which makes it suitable for softer materials. Abrasive waterjet cutting adds abrasive particles, usually garnet, into the water stream, so the jet can cut harder materials with greater force.
Types of CNC Water Jet Cutting Machines
CNC water jet cutters can be classified by their axis movement and cutting capability. In most manufacturing projects, the axis configuration affects whether the machine can cut straight profiles, flat parts, angled edges, bevels, or more complex shapes.
- One-dimensional waterjet cutting: This setup cuts along a single straight line. It is mainly used for simple trimming, slitting, or straight cutting tasks rather than complex part profiles.
- Two-dimensional waterjet cutting: This is the most common configuration for flat sheets and plates. The cutting head moves along the X and Y axes to create flat profiles, holes, slots, panels, brackets, gaskets, and other 2D shapes.
- 3-axis waterjet cutting: A 3-axis system adds vertical control through the Z axis. It allows better height control between the nozzle and the workpiece, which helps when cutting materials with different thicknesses or uneven surfaces.
- 4-axis waterjet cutting: A 4-axis waterjet system may add limited angular or rotational movement, depending on the machine configuration.
- 5-axis waterjet cutting: A 5-axis system provides more advanced head movement for bevels, chamfers, angled cuts, and taper compensation. It is useful when parts need more controlled edge geometry, especially on thicker materials.
Key Systems in CNC Waterjet Cutting
A CNC waterjet cutting system relies on several systems working together. Each system affects cutting stability, edge quality, and dimensional consistency. In real manufacturing, machine condition and process control matter as much as the basic waterjet cutting principle.
- High-pressure pump: The pump generates the water pressure needed for cutting. Stable pressure helps the jet maintain a consistent cutting force during production.
- Cutting head and nozzle: The cutting head directs the jet, while the nozzle focuses the stream onto the material. Nozzle condition can affect kerf width, edge quality, and cutting accuracy.
- Abrasive delivery system: This system feeds abrasive particles into the water stream during abrasive waterjet cutting. Proper abrasive flow helps improve cutting power and edge consistency on harder materials.
- CNC controller and motion system: The controller guides the cutting head along the programmed path. Smooth motion control helps the machine follow complex profiles more accurately.
- Cutting table and water tank: The table supports the workpiece, while the water tank absorbs cutting energy, reduces splash, and helps control noise during cutting.
How Does CNC Waterjet Cutting Work?
CNC waterjet cutting starts with a digital part design and turns it into a programmed cutting path. The machine then uses high-pressure water, with or without abrasive particles, to cut the material along that path. Although the process looks straightforward, the final result depends on programming quality, cutting speed, pressure stability, abrasive control, and inspection after cutting.
Programming the Cutting Path
The process starts with a digital drawing or CAD file. CAM software imports the part geometry and separates the outer contour, internal cutouts, holes, slots, and lead-in positions. The program then sets the cutting order, usually cutting internal features before the outer profile.
At this stage, the programmer sets the cutting sequence, pierce points, kerf compensation, cutting speed, and nesting layout. These program settings tell the CNC waterjet machine where the jet should start, how it should move, and how the cutting path should offset the kerf width.
Waterjet Cutting Execution
After programming, the material is placed on the cutting table. The high-pressure pump forces water through a small nozzle, creating a narrow and powerful jet. For abrasive waterjet cutting, abrasive particles enter the water stream before the jet reaches the material.
The CNC system moves the cutting head along the programmed path. As the jet contacts the material, it erodes the surface and gradually cuts through the full thickness. The machine follows the profile line by line until the external shape, holes, slots, or cutouts are completed.
Part Removal and Inspection
After cutting, the finished profile is removed from the cutting table. Water, abrasive residue, and loose particles are cleaned from the part surface and cut edges. The part is then checked to confirm that the shape, holes, slots, and edge condition match the drawing requirements.
Inspection usually focuses on the overall size, edge quality, kerf condition, visible taper, burrs, and cut consistency. This final check confirms whether the waterjet cut part is ready for use, deburring, surface finishing, or secondary CNC machining.
Advantages of CNC Waterjet Cutting
CNC waterjet cutting suits parts that need controlled profile cutting without heat, hard tooling, or heavy mechanical force. It can also handle thick sections that may be difficult for many thermal cutting methods. Some abrasive waterjet systems can cut around 300 mm, or about 12 inches, but practical results still depend on material type, edge quality, tolerance, and machine condition.
No Heat-Affected Zone
Waterjet cutting removes material through high-pressure erosion rather than melting the cut edge. In abrasive waterjet machining, heat transfer to the workpiece remains very low, with workpiece temperatures often around 30–60°C under normal cutting conditions. Local temperature may still vary with material type, jet pressure, abrasive flow, cutting speed, and measurement position.
This low-heat cutting action helps protect the material near the cut line from burn marks, thermal distortion, and hardened heat-affected edges. For parts that later need machining, finishing, or assembly, waterjet cutting keeps the cut profile closer to the original material condition and gives the next process a more stable starting point.
Material Integrity and Edge Quality
A waterjet stream cuts by controlled erosion. It does not drag a tool across the workpiece, and it does not burn through the material, so the cut edge can stay relatively clean when the process parameters are set correctly.
This cutting action helps preserve material condition while producing a cleaner edge than many heat-based or force-based cutting methods. Thicker sections may still show striations or slight taper, so some functional parts need deburring or secondary machining.
Precision for Complex Profiles
CNC waterjet cutting follows a programmed path, so the cutting head can move through curves, slots, internal openings, and irregular 2D profiles with controlled motion. For complex flat parts, this helps keep the cut shape consistent across repeated parts instead of relying on manual layout or fixed tooling.
Under controlled cutting conditions, some CNC waterjet systems can reach tolerances as tight as ±0.002 inch, but this should not be treated as a default value for every material or thickness. Profile accuracy is different from precision machining accuracy, so tight holes, threads, bearing fits, sealing faces, and critical assembly surfaces often need further CNC machining.
Customization and Production Flexibility
Waterjet cutting uses a digital path rather than a dedicated die. When a part design changes, the program can be adjusted without building a new die, forming tool, or special fixture for every revision.
Custom parts, prototypes, replacement components, and short-run orders can move through waterjet cutting with less tooling restriction. The process also fits near-net-shape blank preparation before milling, drilling, tapping, surface finishing, or other secondary operations.
Limitations of CNC Waterjet Cutting
CNC waterjet cutting has clear limits when a part needs machined functional features, not just a cut outline. It cannot directly create threads, precision counterbores, bearing seats, flat sealing faces, or highly controlled 3D surfaces. Thick materials can also create more visible taper or edge striation because the jet loses energy as it travels through the material.
Parts with threads, bearing fits, sealing faces, precision holes, or controlled assembly surfaces often need CNC milling, drilling, reaming, tapping, grinding, or finishing after cutting. Waterjet cutting can prepare accurate profiles and near-net-shape blanks, but critical features usually need a secondary process to reach final precision.
What Materials Are Suitable for CNC Waterjet Cutting?
CNC waterjet cutting is suitable for many materials because it does not rely on heat or direct tool contact. Material suitability depends on hardness, thickness, brittleness, flexibility, edge quality requirements, and whether the part requires pure waterjet cutting or abrasive waterjet cutting.
Metals
Metals are commonly processed with abrasive waterjet cutting because the abrasive stream provides enough cutting force for dense and hard materials. The process can cut metal profiles without creating a heat-affected zone, which is useful when the blank will later move into machining, finishing, or assembly.
- Aluminum: Aluminum is suitable for waterjet cutting because it can deform under heat, especially on thin plates or large flat profiles. Waterjet cutting helps keep the edge cooler and reduces thermal distortion before later machining or finishing.
- Stainless steel: Stainless steel is suitable when heat tint, oxidation, hardened edges, or thermal distortion may affect appearance, finishing, or assembly. Waterjet cutting can create stainless steel profiles without the thermal edge changes often associated with heat-based cutting.
- Carbon steel: Carbon steel works well with abrasive waterjet cutting because the process can cut thick plate profiles without flame heat or plasma arc effects. It is often used when heavy steel blanks need profile cutting before further machining or fabrication.
- Copper and brass: Copper and brass are suitable because highly reflective metals can create challenges for some laser cutting setups. Waterjet cutting removes material by erosion, so reflectivity does not affect the cutting mechanism in the same way.
- Titanium: Titanium is suitable when heat-affected zones should be avoided before machining, finishing, or inspection. Waterjet cutting helps preserve the cut edge condition because the process does not melt or thermally harden the material.
Plastics and Rubber
Plastics and rubber can be suitable for waterjet cutting because the process does not rely on heat or direct tool pressure. This helps reduce melting, edge stress, chipping, compression marks, or deformation on flat plastic and rubber materials.
- POM: POM is suitable for waterjet cutting because it can be sensitive to heat buildup during some cutting methods. Waterjet cutting helps maintain a cleaner profile without melting the edge.
- PTFE: PTFE is suitable when the material needs profile cutting without thermal deformation or heavy mechanical force. Waterjet cutting can help preserve the shape of flat PTFE parts used for sealing, insulation, or low-friction applications.
- Nylon: Nylon can absorb heat and deform during some thermal or friction-based cutting processes. Waterjet cutting helps reduce melting and keeps the profile more stable on flat nylon sheets or plates.
- Acrylic: Acrylic can chip, crack, or melt when cutting conditions are not controlled. Waterjet cutting can reduce heat-related edge problems, although support and edge quality still need review for brittle acrylic parts.
- Polycarbonate: Polycarbonate is suitable when heat-based cutting may create edge stress, discoloration, or deformation. Waterjet cutting can form flat profiles while reducing thermal damage at the cut edge.
- Rubber: Rubber works well with pure waterjet cutting because the process can separate flexible material without tool drag or compression. This helps maintain cleaner shapes on soft profiles, pads, and custom rubber parts.
- Gasket sheet materials: Gasket sheet materials are suitable because waterjet cutting can create custom sealing profiles, holes, and slots without hard tooling. It works well for rubber, PTFE, foam, fiber, and other flat sealing materials.
Composites and Carbon Fiber
Carbon fiber sheets, fiberglass panels, laminated composites, reinforced plastic panels, and fiber-reinforced sheets are common composite materials for waterjet cutting. These materials usually contain resin systems, fiber layers, or reinforced structures, so the cut edge can be affected by heat, friction, or poor layer support.
Waterjet cutting avoids direct heat on the resin system and removes material through erosion rather than melting. This helps reduce edge burn and thermal damage, but composite cutting still depends heavily on support and piercing control. If the jet enters too aggressively or the laminate is not held properly, the edge may fray, chip, or delaminate.
Glass, Ceramic, and Stone
Glass, ceramic sheets, porcelain, granite, marble, and stone tiles are hard but brittle materials. They can hold detailed shapes well, but they are sensitive to vibration, impact, edge stress, and unsupported areas during cutting.
For these materials, waterjet cutting is mainly valued because it can follow curved or detailed outlines without thermal cracking or heavy mechanical force. The setup matters as much as the cutting force. Stable support, controlled piercing, and suitable entry points help reduce cracking, chipping, and edge breakage during the cutting process.
Materials That May Not Be Suitable for Waterjet Cutting
Waterjet cutting is not ideal for extremely thin films, highly absorbent materials, unstable laminated structures, or parts that cannot tolerate water exposure. These materials may wrinkle, swell, separate, or lose edge stability under jet pressure.
Some coated or layered materials also need careful review before cutting. If the coating, adhesive layer, or laminate structure cannot resist water, abrasive impact, or edge stress, the cut edge may peel, chip, or delaminate. Material stability under water pressure is the key factor when deciding whether waterjet cutting is suitable.
CNC Waterjet Cutting Compared with Other Cutting Methods
Different cutting methods remove material in different ways. CNC waterjet cutting uses erosion, laser cutting uses focused heat, plasma cutting uses an electrically conductive gas arc, wire EDM uses electrical discharge, and CNC milling uses rotating tools. The right choice depends on material, thickness, edge requirement, geometry, and final precision needs.
Waterjet Cutting vs. Laser Cutting
Laser cutting uses heat to melt or vaporize material along the cutting path. It is fast and accurate for many thin sheet metal parts, but the heat can create oxidation, discoloration, hardened edges, or thermal distortion depending on the material and thickness.
CNC waterjet cutting uses a high-pressure water stream, often with abrasive particles, to erode material instead of melting it. This makes it useful when the part cannot tolerate heat damage, when the material is thick, or when reflective materials create challenges for laser cutting. Laser cutting may still be more efficient for thin sheet parts in high-volume production.
Waterjet Cutting vs. Plasma Cutting
Plasma cutting uses a high-temperature plasma arc to cut electrically conductive metals. The arc can reach around 22,000°C, so the process is fast on thick metal plates but more likely to leave heat distortion, a wider kerf, and rougher edges.
Waterjet cutting works very differently. It removes material through high-pressure erosion, and workpiece temperatures in abrasive waterjet machining are often around 30–60°C under normal cutting conditions. That difference in thermal load is one reason waterjet cutting is more often chosen when cleaner edges and lower heat impact are required.
Waterjet Cutting vs. Wire EDM
Wire EDM cuts conductive materials with controlled electrical discharge between a wire electrode and the workpiece. As a type of EDM machining, it can achieve very high precision and fine detail, especially for tooling, dies, sharp internal features, and tight-tolerance parts.
Waterjet cutting is different because it can process non-conductive materials and larger flat profiles. Wire EDM is usually better for very high precision conductive parts, while waterjet cutting is more practical for broader material compatibility and larger profile cutting.
Waterjet Cutting vs. CNC Milling
CNC milling removes material from selected areas with rotating cutting tools. It can machine pockets, steps, threads, precision holes, sealing faces, controlled depths, and complex 3D surfaces, so it is used to finish functional features that need tighter dimensional control.
Waterjet cutting is better suited for separating flat blanks from sheet or plate material. It follows a programmed 2D path to cut outer profiles, large openings, slots, and rough part shapes, making it useful for preparing near-net-shape blanks before CNC milling.
| Method | Heat Effect | Best Used For | Precision Level |
| Waterjet cutting | No HAZ | Thick plates, heat-sensitive materials, complex 2D profiles | Good profile accuracy |
| Laser cutting | Thermal | Thin to medium sheet metal | High for thin sheets |
| Plasma cutting | High heat | Heavy conductive plates | Moderate |
| Wire EDM | Low thermal/mechanical force | Conductive precision parts | Very high |
| CNC milling | Mechanical cutting | 3D features and tight surfaces | Very high |
Common Applications of CNC Waterjet Cutting
CNC waterjet cutting is used in industries that need clean profile cutting, material flexibility, and controlled part shapes without heat damage. Its role changes by industry, but the process is commonly used for flat components, prototype blanks, structural profiles, insulation parts, and parts that will later move into CNC machining.
Aerospace
Aerospace applications place strong emphasis on precision preparation, material stability, and lightweight structure control. Many aircraft parts use aluminum alloys, titanium, or composite materials, where heat distortion can affect later milling, drilling, inspection, or assembly. Because waterjet cutting separates material without melting the edge, it can prepare stable profiles before tighter CNC machining steps.
Typical uses include aircraft brackets, ribs, panels, support plates, titanium blanks, and composite shapes. In this field, waterjet cutting is mainly used to create accurate near-net-shape blanks, while CNC machining finishes holes, fitted surfaces, and critical assembly features that require tighter dimensional control.
Automotive
Automotive development often moves through fast changes in automotive prototyping, prototype testing, and low-volume production before tooling becomes fixed. Stamping or hard tooling may not be practical when the part shape is still changing, especially for test brackets, chassis plates, EV battery-related plates, interior panels, or custom reinforcement parts.
Because waterjet cutting follows a digital program, a revised drawing can move into a new cut layout without waiting for dedicated tooling. This makes it suitable for prototype validation, replacement components, short-run parts, and automotive components that need frequent profile adjustments during development.
Medical Devices
Medical device manufacturing often requires clean profiles, stable material behavior, and careful preparation for later precision machining. CNC waterjet cutting can help create initial shapes for surgical instruments, device plates, fixtures, and titanium or stainless steel blanks without adding thermal damage to the cut zone.
However, medical-related parts usually need strict finishing, inspection, and surface control after cutting. The waterjet step creates the initial profile, while CNC machining and finishing complete the surfaces, holes, and edges that affect fit, hygiene, and final performance.
Electronics
Electronics applications focus on insulation sheets, coated parts, conductive plates, and layered structures. Heat at the cut edge can damage coatings, leave burn marks, create stress, or deform thin bonded materials.
Waterjet cutting uses non-thermal erosion to reduce heat-related edge damage on electronic components. It helps keep insulation edges cleaner and lowers the risk of burned edges, oxidation marks, or thermal stress on conductive profiles before assembly. Typical uses include insulation plates, enclosure blanks, coated sheets, and precision components before cleaning, deburring, or assembly.
Part Design Considerations for Waterjet Cutting
A waterjet cut part should be designed with the cutting process, edge condition, and later machining steps in mind. A clear drawing, suitable tolerance planning, proper corner design, and machining allowance can reduce confusion before production and help the part move smoothly into inspection or secondary machining.
CAD File and Material Details
A waterjet cutting project should start with a clear CAD file and complete material information. The drawing should show the outer profile, internal cutouts, hole positions, slots, and any areas that need special attention.
You should also define the material grade, thickness, quantity, and surface requirement before production. These details help confirm whether pure waterjet cutting, abrasive waterjet cutting, or another process is more suitable for the part.
Tolerance and Edge Requirements
Not every edge on a waterjet cut part needs the same tolerance. Standard waterjet profile cutting can often hold around ±0.002 inch, depending on material thickness, cutting speed, machine condition, and edge quality requirements. Outside profiles may only require general dimensional control, while holes, slots, mating edges, or assembly locations may require tighter tolerances.
Critical dimensions should be marked clearly instead of applying tight tolerances to the entire profile. If a feature needs a tighter fit than the waterjet process can reliably hold, it should be planned for CNC milling, drilling, reaming, or finishing after cutting. This separates normal profile cutting from functional areas that need final machining accuracy.
Kerf Width and Corner Radius
For waterjet-cut parts, critical dimensions should not lie directly on an uncompensated cut line. The waterjet stream removes material along the path, and the kerf is commonly around 0.030–0.040 inch in many abrasive waterjet cutting projects. Slots, holes, narrow bridges, and mating edges should leave enough room for kerf compensation.
Inside corners also need a practical review. A waterjet stream cannot create a perfectly sharp internal corner because the jet has a physical diameter. Small inside radii, narrow bridges, and fine slots should be checked before cutting to avoid weak edges or shape distortion.
Machining Allowance
Some waterjet cut parts need extra material left on specific areas for later CNC machining. This is common for holes, bearing fits, flat sealing faces, precision slots, and surfaces that need tight final dimensions.
Machining allowance gives the next process enough material to finish the feature accurately. Without this allowance, the waterjet cut edge may be too close to the final dimension, leaving little room for correction during milling, drilling, grinding, or surface finishing.
Key Factors That Affect Waterjet Cutting Cost
CNC waterjet cutting cost depends on the actual work required to cut the part, not only the material size. Material difficulty, cutting length, profile complexity, order quantity, sheet utilization, and post-processing requirements all affect the final quotation.
Material Difficulty and Cutting Time
Material type, thickness, hardness, brittleness, and part geometry affect cost because they change how long the machine must stay in the cut. Thick, hard, or brittle materials often require slower feed rates, more abrasive control, and more careful piercing, so the cutting time increases.
Part geometry also affects the quoted price. A simple outside profile usually costs less than a part with many holes, slots, internal cutouts, or detailed contours because each pierce point and direction change adds machine time. The more time the machine spends cutting, piercing, and controlling the edge, the higher the waterjet cutting cost becomes.
Quantity and Material Utilization
Order quantity affects unit cost because setup and programming work can be spread across more parts. A single prototype may have a higher unit price, while repeat parts or small batches may become more efficient once the program and layout are confirmed.
Material utilization also plays an important role. Good nesting can place several parts on one sheet or plate with less waste. If the part shape leaves large unused areas, material cost may rise even when the cutting path itself is simple.
Post-Processing Requirements
Waterjet cut parts may need cleaning, deburring, edge smoothing, CNC machining, tapping, surface finishing, or inspection after cutting. These steps add cost because they require extra handling, equipment, and process time.
Cost planning should include the full manufacturing route, not only the waterjet cutting step. A near-net-shape blank may look simple after cutting, but the final price depends on every operation needed to meet the drawing requirement.
How to Choose a CNC Waterjet Cutting Service Supplier?
Choosing a CNC waterjet cutting service supplier should start from your part requirements, not from the machine list. You need to check whether the supplier can review your drawing, control the cut quality, handle your production volume, and support any secondary process after cutting.
Engineering Review Capability
Check whether the supplier reviews your drawing before giving a final quote. A useful review should mention material thickness, profile complexity, small holes, narrow slots, edge requirements, and areas that may need machining allowance.
If a supplier only quotes by material size and cutting length, you may not get enough engineering support for custom parts. A stronger supplier should identify possible cutting risks before production, especially when the part has tight features or later assembly requirements.
Quality Control Process
Ask how the supplier checks waterjet cut parts after production. Basic quality control should cover overall dimensions, hole locations, edge condition, visible taper, burrs, and batch consistency.
You should also confirm whether the supplier can provide inspection reports when the part requires documented quality checks. A reliable supplier should be able to explain how it verifies the finished part, not just claim that the machine is accurate.
Production Flexibility
Review whether the supplier can support your actual order pattern. Some projects need one prototype first, then revised samples, then a small batch or repeat order. Others may include several part sizes, materials, or thicknesses in one request.
A suitable supplier should handle these changes without losing communication or quality control. If your project may change during development, choose a supplier that can manage revisions, samples, and repeat batches with a stable process.
Secondary Manufacturing Support
Check whether the supplier can support post-cutting operations if your part needs more than a flat profile. Waterjet cutting may prepare the blank, but holes, threads, sealing faces, fitted surfaces, deburring, finishing, or assembly areas may need additional processes.
For custom mechanical parts, this support can reduce coordination between multiple vendors. If the drawing includes functional features, choose a supplier that can connect waterjet cutting with CNC machining, finishing, and inspection instead of treating cutting as an isolated step.
Conclusion
CNC waterjet cutting is useful when a custom part needs clean profile cutting, low heat impact, broad material flexibility, or a near-net-shape blank before further machining. It can handle complex 2D outlines and thick materials well, but it still has limits when a part requires threads, bearing fits, sealing faces, tight holes, or controlled 3D surfaces.
For custom waterjet cutting, CNC machining, and finishing support, DZ Making can review your drawing, material, thickness, tolerance needs, and quantity before production planning. This helps define a more practical manufacturing route before the part reaches the shop floor.
FAQs
1. Is CNC waterjet cutting accurate?
Yes. CNC waterjet cutting can provide good profile accuracy for flat parts, cutouts, slots, and complex 2D shapes. Final accuracy depends on material type, thickness, cutting speed, and edge quality requirements.
2. How thick can CNC waterjet cutting cut?
Some abrasive waterjet systems can cut around 300 mm, or about 12 inches. Practical thickness depends on the material, machine capability, edge quality, and tolerance requirements.
3. Can waterjet cutting replace CNC machining?
Not completely. Waterjet cutting can prepare outlines, slots, plates, gaskets, and near-net-shape blanks, but CNC machining is still needed for threads, pockets, precision holes, sealing faces, and complex 3D surfaces.
4. Does waterjet cutting create a heat-affected zone?
No. CNC waterjet cutting removes material with high-pressure water and abrasive erosion instead of heat, so it does not create a heat-affected zone like laser, plasma, or flame cutting.
5. What file format is needed for custom waterjet cutting?
Common file formats include DXF, DWG, STEP, and CAD files. A PDF drawing is also useful when it includes dimensions, material grade, thickness, quantity, and tolerance requirements.
6. Do waterjet cut parts need secondary finishing?
Some parts only need cleaning or light deburring. Parts with tight fits, threads, sealing surfaces, or critical assembly areas usually need CNC machining, finishing, or inspection after waterjet cutting.
