Abstract: A rotary cutting saw comprising: a base disk; and a plurality of abrasive segments which are bonded to an outer circumferential surface of the base disk so as to be spaced apart from each other in a circumferential direction of the base disk. The base disk has a plurality of slits which are formed in the outer circumferential surface of the base disk so as to be located between the abrasive segments in the circumferential direction. Each of the slits is defined by a pair of side surfaces opposed to each other in the circumferential direction, and a part-cylindrical surface defining a part of a cylinder whose axis is parallel to the axial direction. The part-cylindrical surface has a circumferential width which is larger than a circumferential distance between the radially inner end portions of the side surfaces. The part-cylindrical surface is smoothly connected to one of the side surfaces without a stepped portion therebetween.

Abstract: In a diamond cutting saw blade, a plurality of slits 1 are formed at regular intervals on the outer periphery of a disc-shaped iron substrate 2, and a plurality of segment chips 3 are fixed onto the outer periphery of the disc-shaped iron substrate 2. Two trapezoidal concave portions 4 which expand outwardly are formed on both sides of the outer periphery of each segment chip 3. Further, a trapezoidal concave portion 5 is formed at the intermediate position of the segment chip 3 on a joint surface of the iron plate 2 so as to expand toward the joint surface. At the corner where a bottom surface 4a and a tapered surface (side surface) 4b of the concave portion 4 formed on the outer periphery intersect, there is formed a curved surface 4c having a radius of 1.0 to 2.5 mm. Similarly, in a concave portion 5 formed in the inner periphery of the segment chip 3, there is formed a curved surface 5 c having a radius of 1.0 to 2.

Abstract: Grinding stones, especially resinous and metallic grinding stones which have a controlled distribution of abrasive grains are made by a novel method, in which electrically conductive layers of such pattern which controls sites to be bonded with the grains are formed on the selected surface of a binder sheet, the sheet is immersed in an electrolytic bath containing metallic ions and the grains, the grains are fixedly mounted on the aforementioned sites by metals deposited on the surface of binder sheet with electric paths between the conductive layers and an opposite electrode in the bath, and a plurality of said sheets are placed in layers and warm or hot pressure-molded. When the binder sheet is made from electrically conductive materials, the pattern of the conductive layers is made by masking.