Manufacturing method of rotary grindstone and rotary grindstone which has been manufactured by the manufacturing method

A method of manufacturing a rotary grindstone having a central hole comprising the steps of:

• attaching a liquid resin to a glass cloth having a weave of twist yarns having a diameter of 0.1 mm and formed in meshes with lengthwise and crosswise lengths of 2.0 mm forming a prepreg having opposing faces;
• pressing the prepreg with resin-coated abrasive grain layers on each of the opposing faces of the prepreg in a press wherein resin-coated abrasive grains of the resin-coated abrasive grain layers have a largest intermediate circumference and are wholly and firmly conjugated in the meshes, wherein the largest intermediate circumference of the resin coated abrasive grains are placed within the meshes and whereby a surface of the resin coated abrasive grains extend through the weave of the glass cloth;
• and
• baking the prepreg with resin-coated abrasive grain layers on each of the opposing faces,
• whereby the rotary grindstone is capable of self-sharpening since the resin-coated abrasive grains are held by the largest intermediate circumference in the meshes and chip rather than fall off so that sharp cutting faces appear, grinding resistance decreases and grinding heat is considerably lower.

A rotary grindstone having a central hole comprising:

• a glass cloth having a weave of twist yarns having a diameter of 0.1 mm and formed in meshes with lengthwise and crosswise lengths of 2.0 mm and opposing faces;
• resin impregnating said glass cloth;
• and
• resin coated abrasive grains covering the opposing faces, with each of said resin coated abrasive grains having a largest intermediate circumference held and conjugated in the meshes of the weave of said glass cloth, wherein a surface of said resin coated abrasive grains extends through the meshes on the opposing faces of said glass cloth so as to chip during grinding,
• whereby the rotary grindstone is capable of self-sharpening since the resin-coated abrasive grains chip rather than fall off during grinding so that sharp cutting faces appear, grinding resistance decreases and grinding heat is considerably lower.