| Questions | 5 |
| Topics | Chucks, Fasteners, Fasteners, Pincers, Rulers |
Electric drills utilize a chuck to hold the drill bit. A chuck's size indicates the largest diameter drill bit that will fit. A chuck is tightened and loosened using a chuck key.
A nail is a short pin-shaped shaft of steel that's typically used to fasten pieces of wood together. It has a flat head on one end and a point on the other. A rivet consists of a cylindrical shaft with a head on one end and a tail on the other. When the rivet is installed, the tail is expanded and reshaped to form another head, creating a dumbell shape that will hold two surfaces together semi-permanently.
Wrenches are used with threaded fasteners like bolts and nuts. A bolt has external threads while a nut has internal threads and this thread pattern combination allows them to lock together and act as fasteners. Nuts come in a variety of configurations including wing nuts which provide appendages that allow tightening and loosening by hand, slotted nuts that use a cotter pin to lock the nut in place and prevent it from loosening, and lock nuts that also prevent loosening via nylon in their threads. Threads are identified by pitch which is the number of threads per inch.
Pincers provide a mechanical advantage that's used to cut, pinch or pull an object. The force applied to pincers is concentrated to a point or to an edge of the tool which allows pincers to be brought very close to a surface. Pincers are typically used for removing objects from a material to which they've previously been applied, for example, to pull nails from wood.
Rulers are used to both measure distance and to draw straight lines. Tape measures are flexible rulers made from cloth or metal and are useful for measuring longer distances and in tighter spaces. Both rulers and tape measures provide similar accuracy, commonly down to \({1 \over 16}\) or \({1 \over 32}\) inch. A steel framing square is made up of a shorter ruler (tongue) and a longer ruler (blade) that meet at a 90° (right) angle. A framing square is often used by carpenters when framing stairs and roofs.