Drill bit - Cutting & Abrasive tools

From top to bottom: Spade, lip and spur (brad point), masonry bit and twist drill bits

      Drill bits are cutting tools used to create cylindrical holes. Bits are held in a tool called a drill , which  rotates them and provides torque and axial force to create the hole. Specialized bits are also available for non-cylindrical-shaped holes.

Drill bit (upper left), mounted on a pistol-grip corded drill

      The shank is the part of the drill bit grasped by the chuck of a drill. The cutting edges of the drill bit are at one end and the shank is at the other.
      Drill bit come in standard sizes , described in the drill bit sizes article. A comprehensive drill bit and tap size chart lists metric and imperial sized drill bits alongside the required screw tap sizes.
The term drill may refer to either a drilling machine or a drill bit for use in a drilling machine. In this article , for clarity , drill bit or bit is used throughout to refer to a bit for use in a drilling machine and drill refer always to a drilling machine.

Diamond blade - Cutting & Abrasive tools

      A diamond blade is a saw blade which has diamonds fixed on the blade's base to use the diamonds to cut hard or abrasive materials. There are many types of diamond blades and they have been applied in many industries , for example , construction industry to cut stone , concrete , asphalt , glass and ceramics , IT industry to cut semiconductor materials and gem industry to cut gem stones including diamonds.

Chisel - Cutting & Abrasive tools

    A chisel is a tool with a characteristically shaped cutting edge (such that wood chisels lent part of their name to a particular grid) of blade on its end , for carving or cutting a hard material such as wood , stone or metal. The handle and blade of some type of chisel are made of metal or wood with a sharp edge in it.
      In use , the chisel is forced into the material to cut it. The driving force may be manually applied or applied using a mallet or hammer. In industrial use , a hydraulic ram or falling weight (trip hammer) drives the chisel into the material to be cut.
      A gouge , one type of chisel is used , particularly in wood working , wood-turning and sculpture to carve small pieces from the material. Gouges are most often used in creating concave surfaces. A gouge typically has a ' U '- shaped cross-section.

Bolt cutter - Cutting and abrasive tools

     

Bolt cutter

      A bolt cutter , sometimes called bolt cropper , is a tool used for cutting chains , padlocks , bolts and wire mesh. The original use for bolt cutters was as the name suggests to cut bolt seals from shipping containers at the delivery point. It typically has long handles and short blades with compound hinges to maximize leverage and cutting force. A typical bolt cutter yields 20kilonewtons (4,500lbf) of cutting force for a 250newtons (56lbf) force on the handles.
      There are different type of cutting blades for bolt cutters including angle cut , center cut , shear cut and clipper cut blades. Bolt cutters are available usually in 12 , 14 , 18 , 24 , 30 , 36 and 42 inches in length. The length is measured from the tip of the jaw to the end of the handle.

      * Angle cut has the cutter head angled for easier insertion. Typical angling is 25
         to 35 degrees.
      * Center cut has the blades equidistant from the two faces of the blade.
      * Shear cut has the blades inverted to each other (such as normal paper scissor
         blades).
      * Clipper cut has the blades flush against one face (for cutting against flat
         surfaces).

      Many companies manufacture bolt cutters with fiberglass handles which can be used for cutting live electrical wires and are extremely useful during rescue operations. The fiberglass handles have another advantage of being lighter in weight than the conventional drop forged or solid pipe handles.