Is die casting cheaper than CNC?

Jul,10 2024

Die casting and CNC (Computer Numerical Control) machining are two different manufacturing processes, each with its own cost structure, advantages, and disadvantages. The cost-effectiveness of either method depends on several factors such as production volume, material, complexity of the part, and required tolerances. Here’s a comparison to help determine which process might be cheaper in different scenarios:

 

 

Die Casting

 

Advantages:

Cost per Part: Die casting becomes cost-effective for high-volume production due to lower per-part costs once the initial tooling is made.
Complex Shapes: Can produce complex shapes with intricate details and thin walls that would be difficult or expensive to achieve with CNC machining.
Material Utilization: Less material waste compared to CNC machining, especially for complex geometries.

 

Disadvantages:

Initial Cost: High initial tooling costs due to the need for custom dies, which can be expensive.
Lead Time: Longer lead times for the creation of the die.
Material Limitation: Typically used for metals like aluminum, magnesium, and zinc, limiting the range of materials.

 

 

 

CNC Machining

 

Advantages:

Flexibility: No need for custom tooling, making it ideal for prototypes, small batches, and custom parts.
Material Variety: Can work with a wide range of materials, including metals, plastics, and composites.
Precision: High precision and tight tolerances can be achieved, suitable for critical components.

 

Disadvantages:

Cost per Part: Higher cost per part, especially for high volumes, due to longer machining times and material wastage.
Complex Shapes: More complex shapes can significantly increase machining time and cost.
Material Waste: More material waste compared to die casting, as parts are cut out from solid blocks.

 

 

Cost Comparison

Low to Medium Volume Production: CNC machining is typically cheaper for low to medium volume production because it doesn’t require expensive tooling.
High Volume Production: Die casting becomes more cost-effective as production volumes increase, amortizing the high initial tooling costs over a large number of parts.
Part Complexity: For simple parts, CNC machining might be cheaper regardless of volume. For complex parts, die casting can be more economical at higher volumes.
Material: If you need to use a material not suitable for die casting, CNC machining will be the necessary choice, even if it’s more expensive.

 

 

In summary, die casting tends to be cheaper for high-volume production of complex parts with suitable materials, while CNC machining is more cost-effective for low to medium volume production, prototypes, and parts requiring high precision or materials not suitable for die casting.