Why Choose CNC Machining for Rapid Prototyping?

Have you ever wondered, “What does CNC stand for?” CNC machining, or CNC manufacturing, is a process using computer numerical control (CNC) machines, which are tools such as mills and lathes guided by computer instructions that control the precision of the instruments.

What is CNC Machining?

CNC, or computer numerical control machining, is a widely used manufacturing process that uses automated, high-speed cutting tools to form designs from metal or plastic stock. Standard CNC machines include 3-axis, 4-axis, and 5-axis milling machines, lathes, and routers. Machines may vary in how CNC parts are cut—the workpiece may remain in place while the tool moves, the tool may remain in place while the workpiece is rotated and moved, or both the cutting tool and workpiece may move together.

A skilled machinist operates a CNC machine by programming the tool path according to the geometry of the final machined part. Part geometry information is provided by CAD (Computer Aided Design) models. CNC machines can cut virtually any metal alloy and hard plastic with high precision and repeatability, making custom-machined parts suitable for virtually every industry, including aerospace, medical, robotics, electronics and industrial.

What is a CNC machine?

CNC machining creates parts and components that would not normally be created manually. A set of prompts fed into a computer can produce complex 3D products. CNC machines remove material from base parts by drilling, milling, turning or other types of operations to create shapes, angles and finished products.

The answer to the question "What is CNC?" is to think of the process as a fusion of technology and physical tools. The computer takes input from the CNC machinist, who translates the drawing into a programming language called G-code. The CNC machine then indicates to the tool the speed and movement to follow to create the desired part or object.

Computer numerical control or CNC machining offers many advantages in terms of speed and precision in the manufacture of durable products. Let's take a closer look at CNC machining and why you should choose it for rapid prototyping.

1. Many different materials are available

While processes such as 3D printing are usually suitable for plastic polymers, CNC machining is suitable for a wide range of different materials. Aluminium and aluminium alloys are the most common materials used in CNC machining, but many other materials are available. CNC machines can also use brass and stainless steel, as well as non-metallic materials such as plastic, wood and foam. This makes it easy to build prototypes with hardness, tensile strength, wear resistance and other important characteristics.

2. Precise tolerances

As the name implies, CNC machining is controlled by a computer programme. Essentially, the machine uses a CAD drawing file to create a project from a solid piece of material. Although machines can sometimes malfunction or make errors, they are more accurate than the most skilled human operator.

As long as the machine is set up correctly and the design file is correct, CNC machining can produce products with very tight tolerances. Some CNC machines are capable of achieving tolerances close to +0.05 mm or 50 microns. This accuracy makes it easy to create prototypes exactly as you envisage them, with intricate details, multiple components or whatever design features you need.

3. Fast turnaround

CNC machining is an efficient process that can provide you with hundreds of units in a very short period of time. After refining the design files and setting up the process, the machine will work quickly and accurately. While 3D printing may take hours to produce a single unit, CNC machining can produce dozens or hundreds of units in the same time frame.

4. Mimicking the finished product

Some prototypes are designed to simply mimic the look of the finished product, while others are designed to mimic its form and function. When you choose CNC machining for rapid prototyping, the prototype will look very similar to the finished product, both in appearance and function.

Depending on your prototype design, you can use CNC machining to build a single finished part, or multiple parts to assemble the prototype. Other rapid prototyping processes, such as 3D printing, usually produce a visual representation of the prototype or component. On the other hand, products manufactured by CNC machining are very similar to those produced by injection moulding, which is often used for mass production. As a result, CNC machining produces durable, functional parts that are very similar to finished, marketable products.

5. Finishing options

As your part is built, there are many finishing options to easily get the look and feel you want for your prototype. This may be particularly important if you want to compare the impact of different finishes on sales value, for example, a painted finish versus a chrome finish. Or you may want to ensure that a particular finish is executed in the way you want it to be, such as a powder-coated part being fully rust-proof. Your prototype can be left as it is, or it can be powder coated, sanded, chrome plated, sandblasted, anodised, etc.

There are many advantages to choosing CNC machining for rapid prototyping. If your product development has reached a stage where a short design is possible, contact us. We can provide you with a quote and help you streamline your design to achieve the most cost-effective CNC machining.