Bored Surfaces

Abstract

The surface described in this section is typical of those generated by the boring process. As Figure 7.1 shows, the surface displays a number of segments or ridges parallel to each other caused by the action of a single-point cutting tool as it cuts successive grooves into the surface. The distance between each groove is related to the feed-rate of the boring tool. The tools used in these processes are typically round-nosed and this feature is easily detected from the figure. Notice that the height of the walls of each ridge on the surface is determined, and limited, by the relationship between the depth of cut of the cutting tool as it passes through the bore and the feed-rate per revolution of the cutter. The uneven height of the walls is primarily caused by variations in the cutting forces which arise at the tool-chip interface as a result of the non-homogeneity of the material which is being cut. The resulting surface can be seen to have a random structure in one direction but it is a highly structured (correlated) trend in the opposing direction.