For a fixed upright-piano geometry, repeating a complete three-dimensional finite-element (FE) analysis for every design adjustment is demanding, yet a single global empirical formula gives little insight into how the load is shared by individual ribs. To address this practical gap, a hierarchical rapid static-assessment method is developed for preliminary screening of the UR121 soundboard. Using the FE baseline to set the reported response scale, 438 discrete string-downbearing forces are distributed among 11 ribs by a normalized, load-conserving rule, from which rib-wise deflection, bending moment, and end reactions are obtained. Candidate changes in rib number and orientation can also be examined without altering the total applied load. A three-level 15/10/5 mm mesh assessment is reported; global deformation differs by no more than 4.5900% from the fine level, while local principal-stress extrema remain mesh-sensitive.
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