CNC is known for precision, but can it cut through metal? Learn the exact cutting capabilities of CNC machinery in this handy guide.
Now synonymous with precise cutting capabilities across multiple materials, CNC (computer numerical control) machining is becoming the go-to cutting solution for numerous industries, applications, and purposes.
But while CNC machines are commonly associated with cutting softer materials like wood, plastic, and foam, the question remains, can a CNC machine perform the same function on metal? And if so, what types? Read to discover the ins and outs of CNC and metal.
Can CNC Cut Metal?
Yes. A CNC machine can cut a variety of metal types with a variation of CNC cutting techniques. CNC milling is the best and most common technique for cutting metal. Titanium, aluminium, brass, and steel are among the most popular CNC metal materials.
According to Allied Market Research, the global CNC metal-cutting market is predicted to reach $83.36 billion in 2030. Experts predict the latest surge across the world comes down to the following areas:
- Manufacturing of defence equipment in the private sector
- Rising development of defence expenditure
- Demand from manufacturing machinery industries
- Increasing requirements of the automotive industry
There are three main types of CNC metal cutting techniques:
- Direct metal removal (DMR)
- Laser cutting
- Waterjet cutting
DMR requires a process of a spinning tool cutting into metal material, while waterjet cutting applies high-pressure water jets. As the name implies, laser cutting uses a high-powered laser to cut through metal. The standard metal for CNC cutting requires the material to be softer than 250 c. However, some CNC mills can cut metal with a 1200 C density.
Can CNC Cut Steel?
Yes, steel is a suitable metal you can cut with a CNC machine. The success of your steel cutting depends on the type of steel and the power of your CNC machine. There are multiple gradients of steel with four main variants:
- Stainless steel
- Carbon steels
- Alloy steels
- Tool steels
Typically, structural steel is applied across CNC machining with qualities of strength, density, and impact rigidity. Steel cutting CNC capabilities go through three main techniques:
- Plasma cutting
- Oxy-fuel cutting
- Waterjet cutting
What’s the Best CNC Method for Metal Cutting?
One of the best CNC metal cutting methods is CNC milling. Rather than rotational speed associated with CNC routing, milling makes cuts through increased torque pressure. For this reason, CNC milling is perfect for performing thicker cuts. The spindle is directed on a linear axis above the workstation, moving in an X-Y formation. This functional design of the machinery allows more space for mills to produce wider cuts.
CNC milling machines are the most suitable for metal cutting and can cut most metals except lead. Lead is considered hazardous and should not be machined unless you’re an approved manufacturer with environmental licenses and certified machining ability. CNC milling machines perform the same functions as CNC routers, with a few distinct operational differences. Routers can be used for softer metals such as aluminium while milling is ideal for harder metals. The CNC mill applies rotational cutting tools but with significantly less speed than routing.
5 Types of Metal Suitable for CNC Cutting
With establishing the potential CNC has for cutting and shaping metal, let’s explore the suitable types of metal materials.
Aluminium is the most common type of metal used for CNC machining. As a softer metal, it offers excellent machinability and versatility while maintaining a decent strength-to-weight ratio. These two types of aluminium are proven materials for CNC cutting:
- Aluminium 6061 – It’s seen as the standard class of aluminium, with impressive corrosion resistance except for chemicals and salt water. Aluminium 6061 is often applied to automotive parts, frames, and other structural components, and is considered a general-purpose aluminium for CNC metal cutting requirements.
- Aluminium 7075 – Compared to 6062, Aluminium 7075 qualifies as the higher grade suitable for durability, such as aerospace parts. However, despite its strength, 7075 proves a more difficult material to apply intricate design.
While containing similar strength and durable qualities to aluminium, magnesium is 35% lighter. As a result, magnesium is more valuable for usage across multiple industries. But for this additional benefit, magnesium is more expensive than aluminium.
Titanium boasts an exceptional strength-to-weight ratio with notable resilience and strength. Titanium is also lightweight and highly workable, making it suited for welding and other fabrication methods. Containing high corrosion and temperature resistance, it’s a reliable choice for aircraft, military, and biomedical industries.
The four main types of steel can all be cut and shaped with CNC capabilities. They all have specific characteristics suiting certain requirements. Here are our two steel CNC recommendations:
The most popular type of stainless steel for CNC machining is austenitic. The chemical structure of this type of stainless steel enables the material to work well with welding and machinery.
- SS304 – A stainless steel with high corrosive resistance, ideal for piping, kitchen utensil and automotive parts. Boasting high formability, this type of steel is the go-to for multiple applications across machinery parts to food handling equipment.
- SS304 – With a sulphur presence, SS303 isn’t very good for cold forming or heat treating but is used widely across multiple machine parts, including shafts, gears, nuts, and bolts.
- SS316 – This type of stainless steel is perfect for architectural, industrial, and automotive purposes. It also has strong yet weldable with remarkable corrosive resistance.
Carbon steel is ideal for welding purposes and is cheaper than stainless steel. With a high grade of strength, carbon steel suits specific applications requiring durability and hardness, such as shafts, bolts, studs, and axles.
Brass is a highly versatile metal suitable for CNC cutting. Obvious applications include musical instruments, home décor, piping and electronic hardware. Brass contains saltwater corrosion resistance and doesn’t become fragile at low temperatures.
Find Metal CNC Specialists for Your Next Project
Before attempting to cut metal with a CNC machine, to avoid damaging the machine or causing any harm to yourself and others, you must first understand the material you’re using and the power of your machinery.
At Midlands CNC, we provide expert CNC milling services across design, manufacture, and construction. To ensure we achieve the best result for your next project, we utilise a reliable network of trusted suppliers to source the right metal materials on your behalf.
So, if you require specialist CNC metal-cutting services, get in touch today.