There are many types of CNC machines, through the function they perform, materials they work upon, and the underlying technology of the machine, but what are the common types of CNC machine?
#1 CNC Lathes and Turning Machines
CNC lathes work by rotating a workpiece against a tool that can cut into it. The material is removed from the workpiece by feeding it into the tool at a predetermined angle. The tool is secured to the machine by a collet and moves in either linear or rotational motion.
#2 CNC Milling Machines
Milling machines use cutting tools that move in all three dimensions, removing material to achieve the desired part shape. A block of material (called the workpiece) is placed on a moving table below the cutter. The cutter is mounted on a moving arm (called the spindle) that moves in three dimensions.
#3 CNC Grinding Machines
CNC Grinding Machine means Computer Numerical Control Grinding Machine, which is a kind of computerized numerical controlled metal cutting machine. It processes metals and other materials with the help of grinding wheel. It can provide high accuracy, better surface finish and can work efficiently.
It is used in various industries like automotive, aerospace, defense etc. where high precision and excellent finish is needed.
#4 CNC Laser Cutting Machines
NC Laser Cutting Machine is a machine for cutting materials by means of a laser beam. The intensity of the laser’s beam allows it to cut through a wide variety of materials such as steel, aluminum, brass, and titanium. The laser beam is created by an electrical current that passes through a gas-filled chamber (CO2 gas) and vaporizes the material in the chamber, which forms the beam.
The CNC Laser Cutting Machine works by directing the output of a high-power laser at the material to be cut. The material 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 CNC laser cutting machines are used to cut flat sheet material as well as structural and piping materials.
#5 CNC Electrical Discharge Machines (EDM)
Electrical discharge machining (EDM) is a process where electrical energy is used to erode material in order to create an electrically conductive part or component. EDM machines can be used for cutting, drilling, welding, and other manufacturing processes that require precision and repeatability.
#6 CNC Plasma Cutting Machine
CNC plasma cutting is a process that uses electrically-charged gas to cut materials like metal. The plasma cutting process is primarily used for steel, but is also used for other metals like aluminum, stainless steel, and copper. Plasma cutting works by sending an electric arc through a gas stream from the torch, which heats the gas to plasma temperature (20,000-40,000 degrees Fahrenheit). The plasma then transfers its energy to the metal being cut and melts it as it blows away. This process creates very little heat distortion in the material surrounding the cut and can be automated with CNC technology. By heating the material to the point of melting and using a high-velocity stream of ionized gas (i.e. plasma) to blow the molten metal away from the cut, leaving an open edge, and they do it with both high precision and speed.
#7 CNC Water-jet Cutting Machine
A CNC water-jet cutting machine is a computer controlled machine that uses high pressure water or abrasive to erode material and create the shape programmed in to the machines computer. Abrasive waterjets can cut thicker, harder materials than pure waterjets.
The process of cutting with a CNC water-jet cutting machine is similar to that of a laser cutter. The difference is lasers produce heat during the cutting process and can damage surrounding materials. Water-jet cutters do not use heat, only force and are therefore highly accurate.
Water-jet cutting machine uses ultra-high pressure water to process workpieces. The pressure of abrasive water jet is up to 6000 bar (60000 psi) while normal pressure is 150 bar (1500 psi). In the process of cutting, the high speed abrasive particles are added into the high speed water flow. The abrasive particles are accelerated up to 200 ~ 600m/s in the nozzle and then ablate the workpiece by crashing into it at supersonic velocity.
Quick Comparison Tables
| Machine Type | Primary Operation | Material Removal Method | Typical Materials |
|---|---|---|---|
| CNC Lathe | Turning cylindrical parts | Cutting tool against rotating workpiece | Metals, plastics, composites |
| CNC Mill | Milling 3D contours | Rotating cutter against fixed workpiece | Metals, plastics, wood |
| CNC Grinder | Precision finishing | Abrasive wheel grinding | Hardened metals, ceramics |
| CNC Laser | Cutting sheet material | High-power laser beam | Metal sheet, plastic, wood |
| CNC EDM | Shaping conductive materials | Electrical spark erosion | Hardened steel, titanium |
| CNC Plasma | Cutting thick plate | Ionized gas plasma arc | Steel, aluminum, stainless |
| CNC Waterjet | Cutting thick materials | High-pressure abrasive waterjet | Stone, metal, glass, composites |
| Specification | Typical Range |
|---|---|
| Maximum swing diameter | 200 to 1,000 mm |
| Maximum turning length | 300 to 3,000 mm |
| Spindle speed | 1,000 to 8,000 RPM |
| Axis configuration | 2-axis to 5-axis |
| Positioning accuracy | 0.005 to 0.01 mm |
| Configuration | Axes | Best For | Relative Cost |
|---|---|---|---|
| 2-axis lathe | X, Z | Simple cylindrical parts | Low |
| 3-axis lathe (with Y) | X, Y, Z | Off-center features, keyways | Medium |
| 4-axis lathe (with sub-spindle) | X, Y, Z, C | Complex parts in one setup | Medium-High |
| 5-axis mill-turn center | X, Y, Z, B, C | Aerospace, medical complex parts | High |
| Application | Why CNC Lathe Is Ideal |
|---|---|
| Shafts and axles | Rotational symmetry |
| Bushings and bearings | Precise cylindrical tolerances |
| Threaded fasteners | Single-setup turning and threading |
| Valve bodies | Multi-axis turning and milling |
| Automotive shafts | High-volume production |
| Specification | Typical Range |
|---|---|
| Work envelope (X x Y x Z) | 500x350x300 to 2,000×1,500×800 mm |
| Spindle speed | 8,000 to 24,000 RPM |
| Rapid traverse | 20 to 60 m/min |
| Axis configuration | 3-axis to 5-axis |
| Positioning accuracy | 0.005 to 0.02 mm |
| Axis Type | Movement | Complexity | Typical Parts | Best For |
|---|---|---|---|---|
| 3-axis | X, Y, Z linear | Simple | Brackets, plates, housings | Cost-effective general machining |
| 4-axis | Adds rotation (A or B) | Moderate | Cams, cylindrical features | Parts needing rotational access |
| 5-axis | Adds two rotations | Complex | Turbine blades, impellers | Complex aerospace and medical parts |
| Specification | Typical Range |
|---|---|
| Grinding accuracy | 0.001 to 0.005 mm |
| Surface finish (Ra) | 0.1 to 0.8 micrometers |
| Wheel speed | 20 to 60 m/s |
| Workpiece materials | Hardened steel, ceramics, glass |
| Type | Application | Best For |
|---|---|---|
| Surface grinder | Flat surface finishing | Precision flat parts, molds |
| Cylindrical grinder | External and internal grinding | Shafts, bearings, bushings |
| Centerless grinder | High-volume cylindrical | Mass production pins, shafts |
| Tool grinder | Cutting tool sharpening | Drill bits, end mills, inserts |
| Specification | Typical Range |
|---|---|
| Laser power | 500W to 12kW |
| Cutting capacity (steel) | 0.5 to 25 mm |
| Positioning accuracy | 0.03 to 0.1 mm |
| Cutting speed | 0.5 to 30 m/min |
| Laser Type | Wavelength | Best Materials | Typical Thickness |
|---|---|---|---|
| CO2 | 10.6 micrometers | Non-metals, wood, acrylic | 1 to 25 mm |
| Fiber | 1.06 micrometers | Metals (steel, aluminum, brass) | 0.5 to 20 mm |
| Nd:YAG | 1.06 micrometers | Thin metals, marking | 0.1 to 3 mm |
| Type | Electrode | Best For | Precision |
|---|---|---|---|
| Wire EDM | Thin wire (0.1 to 0.3 mm) | Cutting profiles through thick parts | 0.005 mm |
| Sinker EDM | Custom-shaped electrode | Mold cavities, blind pockets | 0.01 mm |
| Hole EDM | Tubular electrode | Deep small-diameter holes | 0.02 mm |
| Fast Hole EDM | Rotating tubular electrode | Cooling holes in turbine blades | 0.05 mm |
| Specification | Typical Range |
|---|---|
| Surface finish (Ra) | 0.2 to 3.2 micrometers |
| Cutting accuracy | 0.005 to 0.02 mm |
| Maximum workpiece size | 500x350x300 to 1,200×1,000×600 mm |
| Wire diameter | 0.1 to 0.3 mm |
| Specification | Typical Range |
|---|---|
| Cutting capacity (steel) | 1 to 50 mm |
| Cutting speed | 0.5 to 8 m/min |
| Positioning accuracy | 0.1 to 0.5 mm |
| Plasma gas | Air, oxygen, nitrogen, argon-hydrogen |
| Feature | Plasma | Laser | Waterjet |
|---|---|---|---|
| Max steel thickness | 50+ mm | 25 mm | 200+ mm |
| Cutting speed (medium steel) | Fast | Medium | Slow |
| Edge quality | Good | Excellent | Very Good |
| Heat-affected zone | Moderate | Small | None |
| Initial cost | Low to Medium | Medium to High | Medium to High |
| Best material | Steel plate | Sheet metal, non-metals | Any material |
| Specification | Typical Range |
|---|---|
| Maximum pressure | 4,000 to 6,000 bar |
| Cutting accuracy | 0.05 to 0.2 mm |
| Cutting speed | 0.1 to 5 m/min |
| Maximum material thickness | 200+ mm (steel) |
| Abrasive type | Garnet, aluminum oxide |
| Advantage | Benefit |
|---|---|
| No heat-affected zone | No material distortion or hardening |
| Cuts any material | Metal, stone, glass, ceramic, composite |
| Minimal material loss | Narrow kerf (0.5 to 1.5 mm) |
| No toxic fumes | Clean, environmentally friendly |
| Smooth edge finish | Often no secondary finishing needed |
| Machine Type | Primary Operation | Materials | Accuracy | Cost Range | Best Application |
|---|---|---|---|---|---|
| CNC Lathe | Turning | Metals, plastics | 0.005 mm | $15K-$200K | Cylindrical parts |
| CNC Mill (3-axis) | Milling | Metals, plastics, wood | 0.01 mm | $20K-$100K | General machining |
| CNC Mill (5-axis) | Milling | Metals, composites | 0.005 mm | $80K-$500K | Complex geometries |
| CNC Grinder | Grinding | Hardened metals | 0.001 mm | $30K-$150K | Precision finishing |
| CNC Laser (Fiber) | Cutting | Metal sheet | 0.05 mm | $40K-$200K | Sheet metal cutting |
| CNC EDM | Spark erosion | Conductive hard metals | 0.005 mm | $50K-$200K | Molds, complex internals |
| CNC Plasma | Cutting | Steel plate | 0.2 mm | $10K-$50K | Thick plate fabrication |
| CNC Waterjet | Cutting | Any material | 0.1 mm | $50K-$300K | Heat-sensitive materials |
| Volume | Recommended Approach | Machine Type |
|---|---|---|
| Prototype (1-10) | Job shop outsourcing | Any type |
| Low volume (10-500) | CNC mill or lathe | 3-axis mill, 2-axis lathe |
| Medium volume (500-5,000) | Bar-fed CNC lathe, VMC | Production mill or lathe |
| High volume (5,000+) | Swiss lathe, multi-spindle | Dedicated production machines |
