ABSTRACT
Scraping experiments have been carried out with wedge steel type of chisels on three rock types: artificial lime-sandstones H, A and B. The spacing between the grooves, sawn in the rock discs during sample preparation, was varied. An increase of the spacing between the grooves causes an increase of the width of cut and thus an increase of the volume of cut rock. Wear of the chisel increased with an increase of the width of cut. The shape of the worn chisels after testing was different for different widths of cut. A width of cut, equal to the width of the chisel, caused the chisel to wear in such a way, that a concave wear-flat was formed. The ratio of the radial displacement of the chisel into the rock (cutting depth) to the radial displacement of the support of the lathe (feed) may be a measure of different modes of cutting. This ratio is called the cutting mode ratio.
