Which printing process is generally considered to have higher accuracy?

In the context of 3D printing technologies, stereolithography (SLA) is recognized for its higher accuracy compared to fused deposition modeling (FDM). This difference in accuracy arises from the fundamental principles of how each technology operates.

SLA uses a UV light source to cure liquid resin layer by layer, allowing for very fine details and smooth surface finishes. The light can be highly focused, resulting in parts that have dimensions closely matching the design specifications. The layer resolution is typically much finer than what can be achieved with FDM, enabling SLA to produce complex geometries and intricate detailing that are essential for applications requiring precision.

On the other hand, FDM works by extruding melted thermoplastic filament. While FDM can produce robust parts relatively quickly and cost-effectively, it may not achieve the same level of detail or dimensional accuracy as SLA. FDM can experience issues like layer adhesion problems or slight discrepancies due to the thermal expansion of materials during the printing process.

Thus, SLA's mechanism allows it to consistently provide higher accuracy in its 3D printed outputs, making it the preferred choice for applications demanding fine detail and precision.