Which factor is least likely to contribute to print success in FDM?

The factor least likely to contribute to print success in Fused Deposition Modelling (FDM) is filament age. While filament age can affect the performance of the filament, particularly if the filament has absorbed moisture from the air or has deteriorated over time, it is not as directly impactful on individual print success compared to factors such as nozzle temperature, design complexity, and print bed adhesion.

Nozzle temperature is critical for ensuring that the filament flows properly and adheres to previous layers, as each material has an optimal temperature range for extrusion. Design file complexity can significantly affect print success since intricate designs may require advanced techniques or settings to ensure that they print correctly. Similarly, print bed adhesion is vital for preventing warping or shifting during printing, which can lead to print failure. In contrast, while using older filament can lead to issues such as brittleness or inconsistent extrusion, these issues may not manifest if the filament has been stored correctly and is still within workable conditions. Therefore, filament age is a less direct and less consistent factor in determining the success of a print compared to the others listed.