Abstract: A drill bit comprising a shank having three cutting blades extending radially therefrom with the longitudinal cutting edges of the blades defining a right circular cylinder coaxial with the axis of the shank. At the working end of the shank a countersink cutting point is formed by the cutting edges of the blades sloping together to a common point on the axis of the shank and defining a right circular cone.

Abstract: A method and apparatus for forming solid bodies by removing material from solid workpieces. A workpiece is situated between oppositely rotating tools which remove material from the workpiece, these tools having hollow interiors facing each other and each conforming to the configuration of one half of the finished body. The hollow interiors of the tools have teeth for removing material from the workpiece, and while the tools are rotated oppositely the distance therebetween is due so that from the workpiece a body is gradually formed, this body finally becoming almost completely enclosed within the hollow interiors of the tools, whereupon the latter have the distance therebetween increased so that the body formed thereby can be removed. These tools are adapted to form from a workpiece bodies of full circular or ring-shaped configuration, and the hollow interiors of the tools are provided with raised teeth similar to file teeth, for removing material from a workpiece.

Abstract: The present invention relates to an improved drill bit. In the present invention there are disposed opposite each other on a shank a cutting blade with no relief and a post. The post prevents a center swing and is of a small diameter equivalent to a cutting-in amount reduced.