CNC Programming And CNC Machining Complete Costs Breakdown: all you need to know

This post covers CNC programming costs and CNC machining costs for companies. For a CNC (computer numerical control) machine to function as intended, it needs to execute a set of commands that dictates the movements of its motor, axis, speed, and direction. The machine can understand and perform these commands through computer language coding, and the process of writing commands is known as CNC programming services.

CNC machining is a subtractive manufacturing method where the machine removes parts or layers from the base materials to produce a particular design or space. It is the opposite of the additive method, where the equipment builds a design layer by layer. A CNC machine typically uses G-codes and M-codes to control most of its operations. G-codes control primary functions, such as the positioning of tools, whereas M-codes (M for miscellaneous) determine when the machine should activate and deactivate various machine features.

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Cost of CNC programming

The national median salary for a CNC programmer is $27 per hour, although the rate is around $30 per hour in some states. The average annual salary is $57,250 and can be as high as $72,600. The cost may be higher if you hire a CNC programmer on a per-project basis rather than a full-time employee and depends on the complexity of the job:

This rate only covers labor and doesn’t include the cost of running the machine itself. A 3-axis milling machine costs around $40 per hour, while a 4-axis or 5-axis variant can be anywhere between $75 and $120 per hour. The level of finish (rough or smooth) affects the pricing, and the cost of materials will be billed to the client. 

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How it works

CNC programming allows operators to control, monitor, and automate the movements of a CNC operation. The machine can be a lathe, grinder, laser cutter, plasma cutter, mill, or laser engraving, to name a few. A complete CNC machine system includes a dedicated onboard computer, but some models can also be connected to an external computer.

A qualified CNC programmer must understand how the machine works, the type of materials to process, and the tools necessary for the job. All the specifications about the workpiece dimension, movement of the tools, rotational speed, utilized functions, and machining process (duration and length/depth of cuts) are translated into a series of sequential codes for the machine to understand and follow. An operator then downloads the instructions into the machine, runs a test, improves the codes, and lets the machine execute the commands. 

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CNC processes

Some of the most common CNC machine operations include:

• Drilling: like most other drilling operations, the machine creates cylindrical holes in the workpiece. It often utilizes multi-point drill bits to ensure efficiency. The drill bit rotates perpendicular to the material’s surface to produce vertically aligned holes. Additional equipment, for example, holding devices and specialized operation configurations, can also make angular drilling possible. A CNC drill is like a robotic, computer-controlled, fully-automated power drill. Once set up and ready, the operator doesn’t have to change the bit and position of the workpiece until the next operational sequence.
• Milling: a multi-point cutting tool removes materials from the workpiece to produce the desired shape. In a CNC milling machine, the workpiece and the cutting tool can move in multiple directions and angles to create a complex object with intricate details. Milling helps cut flat-bottomed or shallow surfaces. Cutting tools can change automatically, and the operation may include a drilling process.
• Turning: a typical example of CNC turning is a lathe machine. The workpiece is mounted on the equipment and rotated at high speed along the X-axis. A cutting tool is applied in a linear motion to the surface of the rotating workpiece, removing material around its circumference. It is effective for creating cylindrical parts with threads and tapers.
• Metal spinning: a close cousin to a lathe, CNC metal spinning works similarly, except that it does not use sharp cutting tools. As the “pre-formed” workpiece rotates along the X-axis, a spinning roller is applied to the surface to form the desired design. It does not cut or remove materials but reshapes the workpiece using high-speed friction with the roller. The process resembles traditional pottery making, except the work piece is metal.

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Other uses include plasma- and laser-cutting. A CNC plasma cutter cuts conductive metals with surgical precision using a high-powered jet of hot plasma. A laser cutter is suitable for materials other than metal, including wood. Some people use a lower-powered laser to create an intricate design or engrave a pattern on the surface of soft materials like aluminum, plastic, and even leather.

Types of CNC programming

There are three main types of CNC programming: manual, CAM (computer-aided manufacturing), and conversational. Each has its advantages and drawbacks.

Manual programming

Manual programming is the oldest and most challenging type of CNC programming. An operator has to predict how the machine will respond to or execute the commands. The written instructions must be listed correctly because the machine operates in the specified sequence. A mistake will render the operation inefficient or unable to produce the desired shape. In the hands of experts, manual programming allows the machine to operate in a particular way to build complex shapes.

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CAM programming

CAM programming automatically translates a CAD design into codes for those without in-depth knowledge of CNC machines. Since the software handles the conversion, there is very little (if any) programming skill required on the operator’s part. Some code modifications may be necessary, and the software still gives a range of options to refine the operation. CAM programming is between manual and complete automation, suitable for intermediate-level operators.

Conversational programming

Conversational programming, also known as instant programming, requires hardly any knowledge of programming codes. The operator enters commands in simple language, including only the essential details. The operator must also understand the tools, rotational speed, and workpiece dimensions to use instant programming properly. It is the most straightforward programming to set, but it may not be able to make complex shapes or cuts. 

How Cad Crowd can assist

When it comes to prototyping, this is a rather broad subject. The most beneficial topics for you to research may be iterative design, DFM services, and various manufacturing methods. This knowledge will help to make the process smoother for you and find out how it works today.