How to reduce cost of CNC machining parts?

As in other industries, cost optimization in CNC machining is feasible and can be highly profitable for both the customer and the machining facility.

One of the greatest advantages of CNC machining for many industries is its ability to reduce unit costs, especially compared to traditional milling or turning. Every type of manufacturing can be optimized—parts can be produced faster and more cheaply, and more suitable materials can be used, often never before used in the application.

Specifically, the following key factors directly impact the final cost of CNC machining:

1. Lead Time

Starting CNC machining production takes time—in some cases, a significant amount of time. Preparing CAD files (from technical drawings or vector files) and converting them to G-code can be extremely time-consuming. These files contain the "machining steps" for machining, and preparation can consume significant operator time and require precision and experience. This single step can impact the entire manufacturing process, sometimes even reducing cost-effectiveness (for example, for low-volume parts that could be machined on an automated milling machine or lathe). Labor costs are a significant component of every CNC machining quote.

2. Samples

Before CNC machining begins, operators typically produce samples to verify parameters such as part design, selected cutting tools, surface quality, dimensions, and program accuracy. Sample is also part of the quote and, like the previous step, plays a crucial role in overall cost estimation.

3. Batch Quantity

The machining time for a specific CNC machine is often estimated as a fixed fee. Therefore, the larger the batch quantity, the lower the unit cost is likely to be. The main reason behind this is simple: cost breakdown. For example, the preparation cost for a batch of 100 parts may even approach 50% of the unit cost; this fixed cost breakdown becomes more efficient as the number of parts increases.

On the other hand, CNC technology allows for the rapid restart of completed projects, especially in shops that have already produced the previous batch of parts.

In this case, the primary cost of the manufacturing process will be machining time, which depends primarily on the operator's availability of tested CAM files and parts.

To better understand the complexity of CNC machining process quotes, it's worth mentioning the factors that may affect the cost of a specific order:

CNC machined parts production preparation time—including operator time and software costs (CAD, CAM, etc.);

Machine tool and specialized tooling costs—including equipment maintenance and regular calibration;

The cost of raw materials used in the manufacturing process—typically included in the quote and delivered by the machine shop. This is primarily due to logistics and quality control—specialized CNC machining companies have the tools and experience to inspect materials (for example, the repeatable quality of the alloy blocks used to machine the parts);

Finally, a significant component of part manufacturing costs is machine time—which includes electricity consumed and costs associated with the overall company infrastructure (buildings, etc.).

The above factors combined together constitute the cost of a CNC machining process, which also depends on the type of machining equipment (conventional milling machine, five-axis milling machine, laser cutter, lathe, etc.), the material selected, and the number of units ordered.

How and what can be done to save costs in a CNC machining process?

As mentioned above, a large part of the CNC machining process is the preparation work. Restarting production—especially within the same facility—can result in significant cost savings, largely due to the availability of proven CAM files.

Additionally, there are several ways to reduce the cost of CNC machining parts by increasing productivity by reducing the machining time required to produce the part:

1. Selecting the Right Material

Often, a "good enough" alloy or a material "almost identical to the application" can be a perfect substitute for a "perfectly suitable material for the part." Many parts can be successfully machined from polymers instead of alloys—and this change alone can significantly reduce production costs without compromising the final quality of the product. Of course, such decisions should be made in collaboration with the customer and a professional CNC operator with in-depth knowledge of materials science.

2. Simplifying the Project

Rounded edges, perfect surface finishes, thin walls, or excessively deep holes can all increase machining costs. Complex shapes, on the other hand, can be expensive to machine correctly using a CNC mill. Such shapes require changes to operating parameters and increase machining time.

3. Maintaining tight tolerances

where the project is secure, is another practical solution that can save machining time.

4. Select the Right Material Removal Technology

Not all parts are suitable for machining on a 5-, 7-, or 11-axis CNC milling machine. In many applications, a more "cost-effective" 3-axis milling machine can perform just as well, but at a significantly lower cost.

5. Partner with a CNC shop on an ongoing basis

As mentioned above, restarting already executed projects is more cost-effective. For such applications (e.g., producing another batch of the same part), the primary cost of part manufacturing lies in machining time and material, not the overall process preparation.

6. Good Planning

"Cito" CNC machining orders are typically costly. Scheduling orders in advance can increase machining speed and efficiency (also in terms of cost).

7. Prepare the order well

Converting CAD files to G-code can be time-consuming, but preparing additional CAD files for (manual) technical drawings can be even more time-consuming. This is an often-overlooked way to reduce CNC machining costs, but it's worth keeping in mind.

But remember: reducing CNC manufacturing costs doesn't necessarily have to compromise the quality of the manufactured CNC turned parts.

Professional CNC companies like Nuote Metals handle each order and quote individually, focusing on supporting customers with knowledge and experience every step of the way.

This collaboration results in higher quality and often reduces costs throughout the manufacturing process.

Optimal or Suitable Material?

The final cost of a part is closely tied to the selection of the right material. It's possible to find cheaper alternatives with similar mechanical parameters and applications.

Another approach to finding cheaper materials is to select based on their potential for additional surface enhancement processes, such as aluminum anodizing.

Inexpensive alloys treated with such processes may have a lower total cost than the "optimal alloy type."

Additionally, the right material selection can impact the required manufacturing time.

Machinable materials can significantly reduce costs.

Even making subtle adjustments like these between different alloy families or types can significantly save money in the CNC machining process.

In any case, the final decision to change the material mentioned in the technical specification should be discussed and made jointly by the customer and the machining shop team.

Nuote Metals' expert operators can help you identify these cost-saving opportunities. You can request a free quote from us and, if necessary, we will also provide you with assistance to help you find the most cost-effective solution.