Precision metal stamping is a rapid and cost-effective method for manufacturing a wide range of metal products. But that doesn’t mean it is adequate for every application. To understand if precision metal stamping is suitable for you, you must know how it works and alternative manufacturing methods.
What is Precision Metal Stamping?
Metal stamping starts with a piece of sheet metal. That metal is fed into a die. The metal is then pressed by the die, causing alterations such as a cut, bend, or piercing. The metal undergoes a series of presses through different stages of the die until the part is complete. Each stage of the die will be used simultaneously, so a piece is finished after each press.
Precision metal stamping is very fast and very cheap compared to other methods of metal manufacturing. Stamping can be used to produce dozens or hundreds of parts per minute, with only limited manpower. This allows manufacturers to save on wages and save time.
Metal stamping is also able to make parts to precise specifications. High-quality dies operate with perfect regularity, so every piece should be exactly the same. This is one of the reasons metal stamping is popular for manufacturing parts for the consumer electronics industry – highly consistent parts made at a perfect tolerance at a low cost.
There are three significant limitations to metal stamping – 3D construction, part size, and die construction. Metal stamping uses sheet metal as the starting material. It is possible to develop 3-dimensional features with clever die design, but this will always be limited since the metal is flat. One common approach to overcome this issue
For size, metal stamping can make large parts, but it tends to be more complicated and slower. Any increase in the size of the part will be multiplied by the number of stamping steps. Large parts with complex pressing routines can require prohibitively large assemblies.
Die construction is a notable limitation of metal stamping if considering a small batch of parts. Designing and building a precision die is complex, time-consuming, and expensive. It is impractical to make a die for applications where only a few parts are needed. In these cases, manufacturers generally prefer CNC.
What is Computerized Numerical Control (CNC)?
Computerize Numerical Control (CNC) is a method of shaping metal that relies on starting with a piece of metal and machining it into a desired shape using a computer-controlled drill. First, a design is added to the computer, then a block or sheet of metal is positioned within the machine. Once the program is engaged, the computer will use the drill to shave away all the necessary metal until a final shape is achieved.
CNC’s greatest strength is flexibility. This method can make complex 3D objects and can be used to manufacture almost anything you can imagine. Not only can you make a wide range of products, but you can also switch between projects quickly as long as you have the appropriate designs. No specialized or custom equipment is needed to start working on a new part. High-quality CNC machines are also highly accurate, meaning you can use demanding tolerances when designing your product.
While CNC’s versatility is appealing, the method does have several significant drawbacks. Compared to metal pressing, CNC is incredibly slow. A precision metal press can make dozens or hundreds of parts in the time it takes a CNC to make a single piece. CNC also requires at least one dedicate attendant, meaning that the manpower requirements are pretty high. Together, this means that CNC is much more expensive than metal stamping.
As mentioned above, CNC machines use a drill to shave metal from a solid piece to manufacture the final part. There are some alternatives to a metal drill, such as a plasma cutter or a water jet. While there are some advantages and disadvantages to these alternative methods, they are fundamentally the same fabrication method. None can avoid CNC’s issues with speed and cost relative to metal stamping.
What Is Metal Casting?
Metal casting is the oldest method of manufacturing metal products on this list. Molten metal is poured into a mold and then allowed to cool and harden. The final piece will be a solid metal product.
Casting is most often used for medium-to-large-sized articles that do not require tight tolerances. Metal casting is popular for cookware because having a continuous piece of metal encourages even heating. Parts like automotive bodies can be made using casting to get large, complex 3D shapes.
Metal casting has many limitations. It is challenging to make small, detailed parts with metal casting. Molten metal cannot wholly fill thin channels, meaning any small pieces will be uneven and inconsistent. Metal also contracts as it cools, meaning it does not hold the exact shape of the mold. For these reasons, metal casting is not often used for manufacturing parts with strict tolerance requirements.
Metal casting is also slow. Heating and cooling metal take time, so manufacturing speed is often limited by the number of molds available. Controlling the extreme temperatures needed to melt metal requires stringent safety measures, which further slows down production. Fabricating molds also takes time, so switching between projects takes longer than CNC-based methods.
The cost of metal casting tends to be higher than some alternatives. A lot of energy is required when melting metal, which adds to operational costs. The personnel and equipment requirements are also demanding.
Overall, casting is only suitable for a narrow range of applications.
Combining Manufacturing Methods
Of course, it is possible to benefit from each manufacturing approach by combining them. For example, it is possible to create parts using precision metal stamping, and then complete some final details using CNC. Many complex metal products use some parts made with metal stamping, some with CNC, and others that are cast. Good planning and engineering are essential for engineering the best products possible.
Do you have questions about whether you project is suitable for precision metal stamping? Talk to Gold Precision. We are experts in helping our customers manufacture a wide range of parts. Our team has over 20 years of experience in the metal stamping industry.
Contact us today to get a free consultation.