Precision metal stamping/ CNC and metal casting are three distinct but complementary processes in metal fabrication. Precision metal stamping involves the use of specialized dies to form sheet metal into precision parts with high accuracy. This process is particularly suited to the mass production of complex parts.
CNC machining, on the other hand, uses computer-controlled tools to remove material from a workpiece to produce highly detailed and complex shapes. CNC machining is versatile enough to produce prototypes and small batches. Metal casting, on the other hand, involves pouring molten metal into a mold to form three-dimensional shapes after the metal has solidified.
Each of these processes has its own unique use in manufacturing, providing flexibility and precision in a wide range of applications. Which process to choose depends on factors such as the complexity of the part, production volume, and material requirements.
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What is Precision Metal Stamping?
Metal stamping begins with the processing of sheet metal, which is first fed into a die. First, the die cuts, bends, or perforates the metal. Then, the sheet metal is repeatedly passed through the different steps of the die until the part is complete. Each part of the die is used at the same time, so each press completes a part.
Precision metal stamping is very fast and inexpensive compared to other metal fabrication methods. With only a few people to operate it, metal stamping can produce dozens or even hundreds of parts per minute. This saves companies time and money in production.
Metal stamping can also create parts that meet precise specifications. When you use good molds, they should always make the same parts. So every part should be exactly the same. This is one of the reasons why metal stamping is often used to make parts for home electronics: it produces very consistent and exact-fit parts at a low cost.
Of course, precision metal stamping also has some limitations. It can’t be used for three-dimensional manufacturing, parts can’t be made very large, and molds can’t be made very quickly.
Sheet metal is the basis of metal stamping. With clever mold design, three-dimensional shapes can be made, but metal is always flat and therefore can be limited.
Although metal stamping can make large parts. However, the production process can be more complex and take longer. The larger the part, the number of stamping steps will increase accordingly. Large parts that require complex stamping procedures may require larger systems to handle.
When you only need to produce a few parts, mold making is a big problem in metal stamping. Designing and manufacturing accurate molds is very difficult, takes a long time, and is expensive. For tasks that require only a few parts, it is impossible to make molds. In this case, most manufacturers choose CNC.
What is Computer Numerical Control (CNC)?
Starting with a bit of metal and machining it into the shape you want with a computer-controlled drill is computer numerical control (CNC). A program is first entered into the computer, and then a block or sheet of metal is placed into the machining machine. When you start the program, the computer controls the drill to cut away all the necessary metal until the shape is correct.
The great thing about CNC is that it’s adaptable. You can make almost anything you can think of with this method. It can make complex 3D models. You can make a lot of different things, and with the right design, you can quickly switch between jobs. To start making a new part, you don’t need any special or unique tools. You can use tight tolerances when making your products because high-quality CNC machines are also very precise.
While the flexibility of CNC is attractive, there are some major drawbacks to this method. CNC machining is slow compared to metal stamping. In the time it takes a CNC machine to make one part, a precision metal press can make more than one part. In addition, CNCs require at least one full-time assistant, which means relatively high staffing requirements. All of this means that CNC machines cost much more than metal stamping.
As mentioned earlier, CNC machines use a drill to plane metal off of a solid part to make the final part. Plasma cutters or water jets are some of the tools that can be used instead of metal drills. There are pros and cons to each of these different manufacturing methods, but at their core, they are all the same manufacturing method.
What is Metal Casting?
Metal casting is the oldest way to make items from metal. Molten metal is injected into a mold and then allowed to cool and harden. The final part will be made of solid metal.
Casting is primarily used for medium to large items that do not require great precision. Cast metal is often used to make cookware because the single piece of metal helps the heat spread evenly. Casting can be used to make large, complex, three-dimensional shaped parts, such as car bodies.
There are many problems with metal casting. Metal casting makes it difficult to make small, delicate parts. This is because the molten metal cannot completely fill the thin channels. So any small parts will be uneven and won’t fit together well. The metal also shrinks as it cools, which means it can’t hold the exact shape of the mold. Because of these problems, metal casting is not usually used to make things that need to be very precise.
Metal casting takes a long time. Since it takes time to heat and cool the metal, the number of tools available often limits the speed of manufacturing. Strict safety rules must be followed in order to control the high temperatures required to melt the metal. This further reduces the speed of production. Making molds also takes time, so switching between jobs takes longer than with CNC methods.
In most cases, metal casting costs more than other methods. Melting metal requires a lot of energy, which raises the cost of doing business. The need for personnel and tools is also high.
Overall, metal casting can only be used for a few different tasks.
Combining Different Fabrication Methods
Of course, it is also possible to mix different fabrication methods in order to maximize their usefulness. For example, precision metal casting can be used to create parts and then CNC machines can be used to finish the details. Some of the many complex metal products are stamped parts, some are CNC-cut parts, and some are cast. It takes good planning and engineering to make the best product possible.
Do you want to know if your job can be done with precision metal stamping? Ask Yonglihao Machinery, we know how to help our customers manufacture a large number of different parts. Our team has extensive experience in Custom metal stamping. Call us today for a free estimate.