Factors Affecting CNC Machining Cost
CNC machining is a type of manufacturing that utilizes digital codes to create parts. CNC machining has many advantages, for example, it can increase the speed of part production and reduce batch production time when producing identical parts. Since it is controlled by a computer, it can also reduce human errors in the manufacturing process. CNC machining is also the preferred choice for producing precise and complex parts. CNC machining costs can vary depending on different factors listed below, including machining technician salary.
1.CNC Machine Cost
The machining cost varies with the type of machine. There are mainly two types of machines that are used to manufacture CNC machined parts i.e. 3-axis and multi-axis machines. The machine cost also depends on various factors like the size and weight of the machine, speed, power and machine configuration. CNC milling is more expensive than other types of machining operations due to the more complex parts involved. The machining charges increase with the number of axes of the milling machine. For example, in case of 5-axis machining, it costs more compared to 3-axis machines.
2.Machining Time
The time required for the complete machining of any CNC machined part also plays an important role in the calculation of CNC machining cost, the longer the machining time, the higher the machining cost, which increases the basic setup cost. Software such as CAM that requires a 3D CAD design model can provide an estimate of the time required to complete a project. Projects with a high degree of complexity require more time to complete.
3.Labor
One of the advantages of CNC machining over manual machining is that it reduces the amount of labor involved in manufacturing. The primary cost of labor is the experts who design the 3D CAD design model for machining, which increases with the complexity of the desired product. This cost remains the same even if you need to manufacture more parts, which will reduce the machining price per part. However, the additional cost is the labor to operate the CNC machine, which increases with the time required to complete the machining of the part. If the part is assembled, finished, and post-processed by hand, the additional cost is added to the labor cost. If the finished product is delivered from the machine shop to a customer in a different location, additional labor costs are also added.
4.Shape Complexity and Size
Machining costs also increase with the complexity of the CNC machined part. More complex parts may require more process operations, different tools, and more production time. Part features like sharp internal angles, deep cavities, or thin walls increase CNC machining costs. Designs with simple features are easy to manufacture and can also save manufacturing time. Larger parts require more raw materials and time to make, so they will cost more than smaller parts.
5.Material Cost
Material cost is also essential when calculating CNC machining costs. The price of the final product manufactured by CNC machine tools depends on the type of material required to make the product. Plastic or aluminum materials will cost less to machine than stainless steel because plastic materials are cheaper and less durable. Since in CNC machines, materials are removed from solid blocks to make 3D objects. Therefore, more raw materials will be required than the final product.
Machinists purchase materials in the form of solid blocks and calculate the cost of each block of the product. The most commonly used metals in CNC machining are aluminum, stainless steel, and brass. Most machinists use aluminum in CNC machines due to its economical price and excellent machining properties. Stainless steel and brass have poor machinability relative to aluminum, so they cost more. Titanium alloy is the most expensive of all these metals, so the machining cost of this metal will be the highest because it may require some special tools to make the part. In the case of plastics, most materials are less expensive, the cost of the tools required is also lower, and the time required to process plastics such as nylon, Delrin, and ABS is also shorter.
6.Surface treatment
For some products, surface treatment is required, which also leads to an increase in the price of the final product. In order to improve the aesthetics of the final product and remove any scratches caused by the processing process, you may need to provide a good finish such as polishing. Other finishing processes may also include coating, anodizing, painting, chrome plating, galvanizing, etc. The inclusion of any of these finishes will add additional costs to the price of the final product.
7.Tooling costs
In some manufacturing situations, standard tools are not useful, so custom tools are required, which also increases the manufacturing cost of using CNC machines.
8.Tolerances
When manufacturing products with tight tolerances, the cost also increases because complex machines are required to manufacture parts with tight tolerances. Sometimes you may need to manufacture holes or cavities with tight tolerances, which may cause burrs on the surface and will take more time to reduce it.
9.Quantity
The quantity of the order greatly affects the cost of the final product. It is true that the total cost will increase with the number of finished parts required, but the cost per part will decrease.
There are various ways to manufacture the products we want, such as 3D printing and CNC machining. Every customer wants affordable products from manufacturing companies. This article discusses different factors to calculate machining costs and reduce the expenses of your product.