Die Cast vs CNC Machined Enclosures: Which Is Better for Production?
Both processes make aluminum enclosures. They differ in almost everything else: how the part is shaped, what tolerance you can hold, how the surface looks, what it costs to start, and what it costs per part at volume. The right answer depends on your annual quantity and your accuracy requirements.
How the part is formed
Die casting fills a steel mold cavity with molten aluminum under pressure, so the part is defined by the mold and its draft angles. Internal features must be draft-free or use slides and cores, and undercuts are expensive. CNC machining removes material from a solid blank, so geometry is limited by tool reach, not by draft.
Precision, finish, and what the part looks like
Die cast parts carry visible parting lines, gate marks, and a slightly pebbled cast texture; CNC parts show clean toolpath marks and sharp edges. A CNC part can hold tighter flatness and hole position directly, which matters when the enclosure must mount a PCB, seal against a gasket, or maintain a controlled thermal path.
The economics: tooling versus unit price
Die casting requires a steel mold, which is the dominant early cost, but per-part cost drops sharply at volume. CNC machining has almost no tooling cost, so per-part price stays relatively flat across volumes. The crossover is not a universal number — it depends on part size, wall thickness, feature complexity, and finish requirement — so treat any generic break-even figure as a starting estimate only.
Lead time and design flexibility
A CNC part can be produced in days and redesigned the same week, which is why CNC is usually right for prototypes, early builds, and low-volume products. Die casting requires a mold cycle — pattern, cavity, trial shots, and correction — so it belongs to products whose design has stabilized.
How to decide
Choose aluminum for most brackets, mounts, housings, and internal hardware where weight matters, volume is moderate, and appearance must stay consistent. Choose titanium when the part sees salt spray, high heat, fatigue loading, extreme weight targets, or cannot be coated. If both work technically, prototype in aluminum first and upgrade specific parts to titanium only where testing justifies it.