The variation in the extrusion during printing is highly dependent on the printing pa- To assess the extent of under or over-extrusion, the weight of the printed samples was measured, and the variation between the measured and theoretical values (∆W ) was calculated. Figure depicts the variance of ∆W with respect to composition, with each box representing the distribution of ∆W determined for several printings of a single composition under varied printing conditions. The dashed green line indicates ∆W equal to zero, where the printed sample matches the calculated weight of the design. A positive ∆W value indicates over-extrusion, where the printed sample weighs more than the calculated value of the designed sample, while a negative ∆W represents under-extrusion where the printed sample weighs less than the calculated value of the designed sample. The ∆W box of pristine HPLA is located just below the zero-line while the one that of LPLA is located just above the zero line. This indicates that while most of the pristine HPLA samples under-extruded, most of the LPLA samples over-extruded. Considering the higher viscosity of the HPLA compared to that of LPLA, it is expected for HPLA to exhibit more under-extrusion compared to LPLA. When NC incorporated into HPLA, ∆W boxes of the HPLA/NC nanocomposites shifted entirely below the zero line, and the position of the median and the box moved lower as the NC content increased in the composition. It is important to note that 76% of the HPLA/NC samples failed to print which includes some of the HPLA/1.0NC samples, and the majority of the HPLA/3.0NC samples. In general it could be concluded that altough, the introduction of the NC did not increase the viscosity of the nanocomposites (Fig. ), the increase in the storage modulus and 20 thermal degradation (Fig. ) could collaboratively acted and result in under-extrusion while making printing impossible after some point.