CNC Milling vs. Manual Milling

When it comes to manufacturing various parts for different equipment—from flat washers for plumbing to aviation engine parts—several approaches exist. CNC (Computer Numerical Control) milling is a digital manufacturing technology. It uses special software to guide the equipment to produce highly precise components. 

The majority of work for CNC parts manufacturing is done by programming completed separately from the machine, which is operated through automation. Manual milling, on the other hand, involves the work of a skilled operator. 

While it may seem that CNC milling is an obvious choice for spare part manufacturing in the 21st century, many companies still use manual milling. What are their reasons for maintaining this older approach? Let’s review the benefits of each method. 

Advantages of CNC Milling 

CNC milling is a more advanced method of parts manufacturing. It offers numerous benefits for the machining business as well as OEMs who outsource the production of their equipment components. 

  • High precisionThe precision of CNC milling machines is higher than that which can be achieved through even the most skilled human operator. Computer controls allow for minute precision that simply isn’t possible through hands-on manipulation of tools. The machine produces components according to detailed parameters determined by the software.
  • High production volume – CNC milling machines can manufacture thousands of components in a short amount of time. By tuning the software, the operator can create large lots of different products.
  • Lower learning curve – CNC milling machines require the operator to have minimal knowledge about the actual mechanics of the process. The machine does the job entirely. However, the process does require precise programming skills. 
  • Identical products – CNC milling can also produce numerous identical components over and over again within a reasonable period of time. This is extremely advantageous for specialty components and parts that can’t be economically crafted through stamping press or standard tool-and-die methods.  

Advantages of Manual Milling 

Even though CNC milling seems to be the best choice for many projects, manual milling is still widely used by many companies. Several cases exist when manual milling is the best choice since it comes with a number of advantages.

  • Low cost – CNC milling equipment is expensive. Not all companies can bear the costs, especially when just starting the business. Manual milling machines are cheaper and don’t take up as much space as their CNC counterparts.
  • No programming – In order to tune the CNC milling equipment, you need to have skilled programmers doing the job. Such is not the case with manual milling. However, you need to hire skilled operators.
  • Fast manufacturing – While it takes the CNC milling equipment less time to produce larger lots than manual milling, single parts can be manufactured faster on the manual machine. When you need a large lot of identical parts, for example, 10,000 mil-spec stainless flat washers, conventional stamping is one method of manufacture that is fast and reliable. 

Manual milling is great when a single component needs to be manufactured quickly. Meanwhile, CNC milling is an excellent choice for large lots of highly precise identical parts. 

Ideally, a respectable manufacturer should use various machining methods available for its clients’ needs. In many cases, you require both approaches to come up with an ideal component. Manual milling machines can really complement CNC milling equipment, so be sure to consider both options for your production approach.