A pivot assembly (24) is movably connected to a balance beam (22) between a first and second balancing area (34, 36). The pivot assembly (24) defines a pivot axis (B) being movable relative to a center axis (A0) to define a first variable pivot distance (Pd1) and a second variable pivot distance (Pd2) for proportioning a first and second component according to the concurrently and inversely variable first and second pivot distances (Pd1, Pd2). The balance beam (22) presents a proportioning scale (60) which includes a plurality of identical ratios (62) in scale of the first variable pivot distance (Pd1) to the second variable pivot distance (Pd2) for aligning the pivot assembly (24) with a desired ratio of the first and second components. A first and second pair of retainer walls (38, 40) extend upwardly from the respective balancing areas (34, 36) and diverge from one another for abutting and centering a variety of container sizes on the respective balancing areas (34, 36).