Rotary cutting assembly

Rotary cutting assembly for cutting vegetation with whirling filament and comprising:

• A. an elongate lineal shaft extending along a vertical-axis, the longitudinally extending shaft having a bottom-end and also a top-end for removable insertion into a portable manually-held chuck whereby the shaft is powerably rotatable about its vertical-axis;
• B. a disc-like base-plate co-rotatably associated with the shaft and located at the shaft bottom-end, said base-plate including a peripheral-edge lying within a horizontal plane and with the shaft at the substantial geometric center of said base-plate, the base-plate including a pair of transversely extending surfaces including a lower-surface and an upper-surface;
• C. a convolute supply of filament surrounding the shaft vertical-axis and located immediately adjacent a transverse surface of the base-plate, successive leadward portions of said filament supply being horizontally drawable radially outwardly from the vertical-axis and outwardly beyond the base-plate peripheral-edge for cutting vegetation as the shaft rotates;
• D. at least one retainer means attached to the base-plate for removably securing a leadward filament portion to the base-plate, the said at least one retainer being located nearer the base-plate peripheral-edge than to the longitudinal vertical-axis;
• E. axial confinement means for maintaining the stored convolute filament longitudinally confined with respect to the base-plate;
• and
• F. gravimetric balancing means to ensure that the center-of-mass for the combination of base-plate, retainer means, and axial confinement means is located substantially at the shaft vertical-axis.