Abstract: For determining a path of movement of a tool along shoe bottom marginal portions a series of points along such path is selected and information regarding such points stored in the form of digitized co-ordinate axis values by a computer, from which information the path can subsequently be derived. The selected points are spaced by a predetermined distance (which may be the same for each pair of adjacent points) regardless of shoe bottom contour. To this end, when each point is digitized, the tool and shoe bottom are relatively moved apart by the predetermined distance along a first axis, extending heightwise of the shoe bottom. Thereafter in returning the tool and shoe bottom into engagement along said one dimension under operator control, appropriate compensating movement also takes place automatically along a lengthwise axis and/or along widthwise axis.

Abstract: A computer-controlled machine for progressively roughing marginal portions of shoe bottoms comprises a tool carrier on which two rotary roughing brushes (168) are carried side-by-side, and a shoe support (18) between which and the tool carrier relative movement takes place lengthwise, widthwise and heightwise of the shoe bottom. Each tool (168) is mounted so as to "float" heightwise in relation to the tool carrier, resilient means (175) being provided for urging each tool independently downwardly towards the shoe support (18). In this way the pressure applied by each tool to the shoe bottom in the operation of the machine can be controlled and/or regulated. For effecting relative movement between tool carrier and shoe support, numerically controlled motors are provided, operating in response to a programmed instruction. Such instruction can be made using the machine in a path-determining mode.