Minimum part quantity?

500-1000 pieces for cost-effective. Tooling amortized over 5000+.

3m x 2m bath tubs. Truck body panels. Press bed limits.

One mold side can be mirror finish. Opposite side matte.

Tooling yes 1/3 injection cost. Per-part cost higher due to slow cycle.

Learn more about key differences for your manufacturing sourcing needs in China.

Learn more about materials for your manufacturing sourcing needs in China.

Compression Molding vs Injection Molding

Process comparison, cost, part quality differences.

Key Differences

Compression molding: preheated material placed in open cavity, mold closes under pressure (100-500 kg/cm2). Injection molding: material injected into closed cavity. Compression better for large flat parts, thermosets, high-strength composites. Tooling cost: compression $10000-50000 (less complex). Throughput: slower (3-15 min cycles) vs injection (30-60 sec). Fiber orientation more controlled in compression.

Parameter	Compression	Injection
Tooling cost	$10000-50000	$30000-200000
Cycle time	3-15 min	30-120 sec
Best for	Large, thick parts	Complex, thin walls
Material waste	2-5% flash	15-30% runner

Materials

BMC (bulk molding compound): glass fiber + polyester, for electrical and automotive. SMC (sheet molding compound): pre-impregnated glass mat, large panels. Phenolic: heat-resistant, high mechanical strength. Epoxy: composites for aerospace and high-performance. Melamine: decorative laminates, tableware.