CNC vs. Manual Machining: Advantages of Each

Many industries rely on computer numerical control (CNC) machining when it comes to manufacturing.

CNC machining is possible through computer software, which programs the tools and machinery to follow a specific set of instructions to create custom parts from raw material.

A CNC machinist works with these machines and software, ensuring they’re set up properly and running smoothly. Until CNC technology became the primary machining method in manufacturing, industries relied on manual machining, which required one technician per machine.

Manual machining still has a place in the industry, even if it’s less common. Keep reading to find out more about the differences between CNC vs. manual machining!

What Is CNC Machining?

CNC machining is known for its precision and automation, where computer software dictates the movement of factory tools and machinery. This method allows for complex shapes to be created with high accuracy and repeatability, automatically without human intervention, making it ideal for both one-off prototypes and high-volume production.

What is Manual Machining?

Manual machining requires direct operator control and skill to manipulate tools and machinery. It is often used for custom projects, repairs or when the material or design cannot be executed through automated processes. This method allows for a high degree of flexibility and operator input, making it valuable for specialized tasks.

Differences Between CNC Machining and Manual Machining

One of the major differences between the two machining methods is the number of employees needed during the process. With CNC machining, a trained individual can operate several machines at once. With manual machining, each machine needs one technician.

The history of CNC machining dates to the 1940s, when it was first developed by John T. Parsons, who was commissioned by the U.S. Air Force. Later, computer-aided design (CAD) was combined with CNC machining to make further technological improvements. These efforts were led by researchers at the Massachusetts Institute of Technology (MIT).

There are several advantages of CNC machining vs. manual machining, including:

• Uniform results: Programmed machines can manufacture the exact product time and time again.
• Large-scale production: CNC machining can manufacture thousands of pieces in a short amount of time, allowing businesses to scale quickly.
• Safety: The machines are working behind a guard and often a closed, transparent safety door, which helps eliminate the risk of injury.
• Decreased labor: CNC machines can produce components with minimal intervention and effort, which is why one trained worker can operate and monitor several machines at once.

While CNC machining is used by most businesses, there are still instances where manual machining can be a more appropriate approach. Here are some benefits of manual machining:

• Cost effectiveness: Manual machines are less expensive, making them a good option for those new to an industry.
• Short turnaround: It takes less time to produce a component, as there are fewer steps involved than in CNC methods.
• No programming: Operating manual machines does not require programming beforehand, which can help save time. The person operating the machine does not need skills to be able to program and load computer software.
• Great alternate method: If a facility is producing a large amount of goods and tackling big projects, manual machining can be used for smaller projects, which can increase the efficiency of the business.

When it comes to CNC vs. manual machining, each has its unique benefits. Those needing parts to be machined would have to consider what they’d be producing and which process best suits their specific needs.

Advantages of CNC machining

CNC machining stands out for its precision, reliability and efficiency in manufacturing. Here are some of its key advantages:

• High precision and consistency: CNC machines can produce parts with extremely limited dimension variations, ensuring that every product is identical.
• Increased production speed: Once programmed, CNC machines can manufacture parts much more quickly than manual processes.
• Versatility: CNC machinery can produce parts from a wide range of materials, including metals, plastics and composites.
• Reduced waste: Precision and efficient material usage minimize waste produced during the machining process, making CNC eco-friendlier than manual machining.
• Lower labor costs: Automation reduces the need for human involvement, which can lower labor costs.

Advantages of manual machining

Despite the rise of automation, manual machining is important in the manufacturing industry for several reasons:

• Flexibility for one-offs and prototypes: Manual machining is ideal for creating single units or prototypes, offering flexibility that CNC machines can't match.
• Lower cost for small runs: For small batch productions, manual machining can be more cost-effective than setting up CNC operations.
• Simplified maintenance: Manual machines have simpler mechanisms, making maintenance easier and often less costly.
• Skill development: Operating manual machinery requires and cultivates a high level of skill, contributing to the operator’s problem-solving abilities and intimately hands-on understanding of machining processes.
• Immediate adjustments: Manual machining allows operators to make instant adjustments, providing machinists the ability to respond quickly to any issues or changes needed during the machining process.

FAQs

1. What is the difference between CNC vs. manual machining?

CNC machining automates the machining process through computerized control, resulting in precision, speed and the ability to execute complex designs. In contrast, manual machining requires human involvement for operation, making it more labor-intensive and less consistent in terms of precision.

2. What are the advantages of using CNC machines over manual machines?

Using CNC machines offers numerous advantages over manual machines, including higher precision, consistent quality across large production runs and the ability to perform complex cuts and shapes that would be difficult or impossible with manual machining. Additionally, CNC machines can operate continuously without the need for breaks, significantly increasing productivity.

3. How does the skill set of a manual machinist differ from that of a CNC machinist?

The specific skill set of a manual machinist primarily revolves around hands-on operation, setup and maintenance of machines, along with the ability to judge tools and make adjustments on the fly. CNC machinists, however, must possess strong programming skills, an understanding of CAD/CAM software and the ability to troubleshoot and optimize CNC machine operations.

4. Can manual machines perform the same tasks as CNC machines?

While manual machines can perform many of the same tasks as CNC machines, they are generally slower, less precise and require a higher level of operator skill to produce similar results. CNC machines excel in tasks requiring high precision, complex geometries and repeatability.

5. Are there any industries where manual machining is still preferred over CNC machining?

Certain industries, such as custom manufacturing, restoration work or highly specialized small batch productions, may still prefer manual machining due to its flexibility, lower setup costs for one-off items and the unique skill set of experienced machinists that can add a personal touch to the finished piece.

Learn Various Machining Methods at UTI

While CNC machining is the method of choice in most cases, industry training can teach you how to operate all types of CNC machines, and can help you pursue a career in the industry.

The 36-week CNC Machining Technology program offered at Universal Technical Institute in Mooresville, North Carolina, can provide the hands-on, high-tech skills needed to prepare for a career as a CNC machinist.⁸⁵ The program’s courses cover a range of machine types and operations, including manual machining. Specifically, there are three machine milling courses:

• Manual Machining Basics: Students are introduced to and learn the skills needed to use manual lathe and milling machines to create various parts.
• Manual Machining on the Lathe: During this course, an understanding of manual lathe threading and taper turning is covered. More skills are introduced so students learn to use manual milling machines for production.
• Manual Machining on the Mill: Advanced manual milling processes are covered during this course, with an emphasis on angular and complex milling operations.

Along with learning manual machining, students gain a well-rounded knowledge of all CNC machining methods needed by entry-level machinists in the industry.

Interested in pursuing this career path? Be sure to request more information here, or call 1-800-834-7308.