Stamping or CNC milling: which manufacturing process is the right choice for your metal parts? For low volumes and complex geometries, milling often wins. However, as volumes increase, the cost picture changes significantly. In this article, we compare stamping and punching with CNC milling in terms of cost, lead time, tolerances, and application scope.

What stamping and pressing precisely entail

In stamping, a press cuts or shapes a component from a metal sheet in one or more strokes. The tool, the die, determines the shape. Once made, that die produces thousands of identical components one after another. Stampings works on the same principle but more often focuses on three-dimensional metal deformation, such as deep drawing or bending. Both processes are designed for repetition.

The mould is the heart of production. At Eurotechniek, we work with precision-made moulds that are suitable for long production runs without loss of quality.

Why CNC milling is less suitable for large series

CNC milling is a machining process. A milling cutter removes material from a block of metal until the desired shape remains. It is precise and flexible, but also time-consuming and wasteful of material.

For a run of a hundred parts, milling is fine. With ten thousand units, the picture changes completely. The machining time per part remains the same, tool wear increases, and material loss accumulates. Furthermore, CNC milling requires a fixed machine capacity per part. You can soon utilise that capacity more effectively with stamping.

The cost advantage at higher volumes

The difference in cost becomes apparent as soon as you compare fixed and variable costs. With die-cutting, you pay for the die once. This investment is substantial but is spread across the entire print run.

Suppose a mould costs €15,000 and you produce 100,000 parts. Then the mould costs are €0.15 per part. The variable costs per cycle are low: a press stroke cycle takes fractions of a second.

With CNC milling, you have no mould costs, but you pay per hour of machine occupancy. For large quantities, this weighs more heavily than the mould investment for punching. Eurotechniek regularly advises customers on the break-even point between milling and punching. For most sheet metal parts, that point is reached quite early in the production run.

Tolerances and repeatability in practice

A frequently heard argument for CNC milling is its dimensional accuracy. Milling can achieve tolerances of a few micrometers. That's true, but stamping is also accurate, especially for two-dimensional shapes. A well-designed die produces part after part within the required tolerance.

Repeatability is even a strong point of die cutting. The die does not change. Each stroke yields the same result, provided the process is properly secured.

When milling, there are more variables at play: tool wear, clamping, and thermal expansion of the machine. These factors necessitate more frequent quality checks for long production runs. With stamping, using precisely calibrated dies generally results in less variation over large quantities.

Cycle times and delivery speed in mass production

Speed is a decisive factor in every purchasing decision. A modern eccentric press makes hundreds of strokes per minute. A single punching part can be produced in less than a second. With a CNC machine, the operation takes minutes per part, depending on the geometry.

As a result, the difference in lead time for an order of 50,000 pieces is enormous. Stamping delivers the batch in days. Milling requires weeks of machine capacity. This makes a significant difference for production planning and inventory management. Customers of Eurotechniek choose stamping partly to guarantee shorter delivery times to their own customers.

Material selection and applications in the manufacturing industry

Stamping and pressing work well with a wide range of metals. Steel, stainless steel, aluminium, copper and brass are all suitable. The thickness of the material partly determines which process and which tooling are required.

For thin-walled parts such as switch components, brackets, contact plates and housing parts, stamping is exceptionally well-suited. Stamping is also used for deep-drawn parts like cup shapes, holders and protective covers.

CNC milling offers more freedom with complex three-dimensional shapes, but that freedom comes at a price that is rarely justifiable in mass production. In the automotive, electrical engineering, and appliance manufacturing sectors, stamping therefore dominates as soon as volumes increase.

Frequently asked questions about die cutting and stamping versus CNC milling

From what volume is stamping more cost-effective than CNC milling?

That depends on the complexity of the part, the material, and the mould costs. As a general rule of thumb, stamping becomes interesting from a few thousand pieces per year. For simple sheet metal parts, the break-even point can already be at five hundred pieces. Eurotechniek will gladly calculate this for your specific situation based on the drawing and desired production run.

Can the press also deliver precise components for precision applications?

Yes. Modern stamping technology achieves tolerances comparable to milling for flat shapes. The accuracy is determined by the die quality and the press settings. For parts with strict dimensional requirements, we work with calibrated dies and carry out sample checks during production.

What are the disadvantages of stamping compared to milling?

The main disadvantage is the limited flexibility after mould production. Adjustments to the mould require adaptation or replacement of the mould, which incurs costs. Milling is also faster and cheaper for single pieces or small prototype batches. Stamping is a process for stability and volume, not for variation and bespoke customisation.

The right choice begins with the right information

Stamping and punching are not a universal answer to every production need. However, for mass production of metal parts, they are in most cases more efficient, faster, and cheaper than CNC milling. The investment in a die pays for itself as soon as volumes increase. The repeatability of the process guarantees quality across the entire series. And the cycle times allow for quick delivery, even on large orders.

Would you like to know if die stamping or stamping is suitable for your parts? Contact Eurotechniek. We will look at your drawing with you and give you honest advice on the most appropriate production process.