How precise can investment casting tolerances be?

Dimensional Precision in Investment Casting

Investment casting is widely used for manufacturing complex metal components that demand exceptional dimensional accuracy and fine surface finish. At Neway Precision, the process typically achieves tolerances as tight as ±0.075 mm for dimensions under 25 mm, and ±0.1 mm for mid-sized parts up to 100 mm. Compared to other casting methods such as sand casting or gravity casting, investment casting provides a superior balance between precision, surface smoothness, and design flexibility.

The precision results from using high-quality ceramic molds formed around wax patterns. These molds accurately replicate fine geometries and internal features, making the process ideal for turbine blades, impellers, and structural components in aerospace and medical applications.

Factors Influencing Casting Tolerance

Several variables influence achievable tolerances. The choice of casting material—such as cast stainless steel, carbon steel, or nickel-based alloys—affects thermal expansion and shrinkage. Mold shell thickness, wax pattern accuracy, and controlled burnout and pouring parameters also play critical roles. For extremely demanding tolerances, Neway’s CNC machining prototyping and precision casting integration allows post-casting finishing to reach sub-0.02 mm precision where necessary.

Surface Finish and Post-Processing Accuracy

Investment casting naturally provides smooth surfaces with Ra values of 1.6–3.2 μm, thereby minimizing machining requirements. To enhance both appearance and dimensional control, Neway utilizes secondary processes, including polishing, heat treatment, and anodizing. These treatments refine surface quality, enhance corrosion resistance, and ensure that each component meets the stringent standards required by the aerospace and automotive industries.

Achieving Consistent Quality

At Neway, every investment casting project is supported by dimensional inspection, coordinate measurement (CMM), and statistical process control (SPC). Through the custom parts manufacturing service, customers receive repeatable precision with optimized tooling design and material selection tailored for critical applications.