Today, CNC machining is one of the most popular machining methods for custom manufacturing, whether you’re looking to create a single prototype or a large-scale mass production run. The priority, then, apart from ensuring the quality of the product, is usually to reduce the cost of manufacturing. This is because projects remain competitive in the marketplace only if the cost of the project is kept at a reasonable level.
In the pricing of CNC machining, the most important factor affecting the price is usually the machining time. The cost of machining time can exceed the cost of materials, design costs, and custom finishes. To prevent losses and save time to market, the only way to minimize machining time is to reduce it.
This article will describe in detail the factors that affect the price of CNC parts and what should be done to make CNC parts cheaper.
What are the factors that generally affect the cost of CNC parts?
Regarding CNC machining, reducing manufacturing costs is usually a top priority. Fortunately, the decisions you make as a designer can critically impact final pricing. By understanding a bit about the factors that affect CNC part costs, you can greatly contribute to reducing those costs.
As a design engineer or project leader looking to customize a part through CNC machining, reducing manufacturing costs and ensuring quality are top priorities. Often the decisions you make can be decisive for the final pricing. If you need to reduce the price of CNC parts, first, you must understand what factors affect the cost of CNC parts. Only if you know enough about the influencing factors can you significantly contribute to reducing production costs for your project.
Here is some background information on each factor that can be used to ultimately reduce production costs:
1. Machining time: This is the main factor affecting the price of CNC parts. Typically the longer it takes to machine a part, the higher the cost. 2.
2. Design Costs: This is primarily used to cover the cost of CAD files and product planning for product design. For rapid prototyping and small quantities, start-up costs can be very high.
3. Material Costs: The material used for the project, the cost of purchasing the material, and the difficulty of machining the material is another important factor that affects the price of a CNC part.
4. Other Manufacturing Costs: Custom CNC machined parts typically have special requirements, such as tight tolerances or thin walls. These usually require specific tooling, additional machining steps, and lower speeds. All of these factors affect machining time and ultimately lead to higher costs.
5. Material Finishes: Adding a finish to a part can improve its appearance and make it more resistant to harsh environments. Additional machining processes can also increase machining costs.
When setting a price for custom CNC machined parts to fit your project and seeking a CNC machining service provider, remember the basic principles quoted by CNC machining service providers: the longer the machining time, the higher the price. The more processes, the higher the price. The price will also be higher if you want to ensure quality and use good materials for the part.
However, design costs also affect the final price of the part. These include costs associated with CAD file preparation and part fixturing. For smaller quantities, these costs can be high. The higher the quantity, the higher the cost shared per part, but in the case of small quantities and rapid prototyping, setup is usually more expensive than the part itself.
A Few Tips for Effectively Reducing CNC Part Costs
Overall, optimizing the part design can minimize the price of a CNC part. This can be accomplished by increasing the radius of the vertical edges inside the part, limiting the depth of the cavity, increasing the thickness of the walls, appropriately limiting the length of the threads, optimizing the threaded holes, and splitting complex parts into simpler, individual parts Reduce wear on the part by selecting only the necessary surface finish and minimizing the number of operating machine setups. Each factor is specified below.
Optimizing Material Selection
Materials not only affect the price of a CNC part, they may also affect its machinability. Therefore staying within budget by switching to cheaper materials better suited to the project’s design performance and machine finish can intuitively reduce the price of a CNC part. If a softer material is chosen for machining, the machining time is reduced, and so is the cost; conversely, the harder or more difficult to machine the material used, the longer the machining time and the higher the cost.
Limit the use of tight tolerances to only the necessary design.
Customized tolerances significantly increase the cost of machined features. When your part designer includes tight tolerances, it’s clear that the part won’t be cheap, especially since the more numerically labeled features in the design (e.g., radii, bores, and chamfers), the more expensive the part will be to manufacture. Those who want inexpensive CNC parts should only do so when necessary.
Typically, CNC machined parts have a tolerance of +/-0.127mm. In most cases, the tolerance can be +/-0.05mm. To eliminate unnecessary costs, it is critical to only assign values to mission-critical features and surfaces. The model should control Other less important features (standard tolerance is +/- 0.005 inches).
Avoid Multiple Surface Finishes
Surface finishes can improve the appearance of your CNC parts and their resistance to harsh environments. Going through multiple surface finishes requires more machining time, and the cost of machining the part increases. Therefore, avoid designing multiple surface finishes on your CNC part machining. Mixing and matching finishes will add more cost. For example, requiring a mix of anodized and chemical film finishes on a part will add several processing steps. The same applies when specifying smooth surfaces in one area and sandblasted surfaces in others.
Avoid Using Too Many Thin-Walled Designs and Extensions
Because CNC parts with thin-wall designs are fragile and thin walls are less resistant to chatter during machining, the machining speed must be reduced. Fracture, deformation, and difficulty maintaining tolerances are the difficulties of thin-wall machining. Therefore, it is important to keep the walls as thick as possible to avoid the complications associated with chatter. Thick walls are more stable and cheaper to machine. Metal parts with wall thicknesses over 0.8 mm and plastic parts with thicknesses over 1.5 mm can be designed as long as weight is not a concern. If thin walls cannot be solved, consider other manufacturing methods more suitable for this type of production, such as sheet metal fabrication.
Order as many quantities at once as possible
The number of parts you order significantly impacts the unit price. Take advantage of economies of scale to reduce overall costs by scaling up to order more of the needed parts. Economies of scale can reduce the unit price of a part by more than 50% for quantities that increase from 1 to 50 or more.
To make custom parts and rapid prototyping for industrial applications inexpensive. First and foremost, understand the factors that affect the price of CNC parts. Also, by following the simple tips above, which are helpful for custom metal and plastic parts and materials that require extra machining time, you can save on your machining time production prices and reduce CNC machining rates.
If you need custom CNC parts, Elimold is a certified CNC machining shop, and when it comes to making CNC parts, no one can beat us regarding quality parts and inexpensive materials. Your satisfaction is our top priority in optimizing your parts and designs. Please request a free quote and learn more about our capabilities and resources. We carry a wide variety of materials such as steel, plastic, titanium, and wood and offer full-time support and quotes to our customers.