Starrett 42-8 Hermaphrodite Joint Calliper, Steel, Flat Leg, 0-8" Range

The Starrett 42-8 lock joint hermaphrodite calliper with fine adjustment has a leg length of 8” (200 mm) but opens to approximately one-third larger than the leg length. Hermaphrodite callipers are used to scribe lines parallel to the workpiece edge, locating and testing centres and other layout work. The legs are made from high-grade steel and are ruggedly constructed and well-finished. Knurled adjusting nut makes the final adjustment after the legs have been set to approximate size and the joint has been locked. The spring washer under the disc maintains proper leg tension when the joint is loosened. Callipers measure the distance between two opposing sides of an object. They make inside, outside, depth or step measurements, according to their type. Callipers are commonly used in architecture, metalworking, mechanical engineering, machining, manufacturing, carpentry and medicine. The simplest callipers have two legs to mark the two points and require a ruler to take the measurement. More complex callipers use two sets of jaws instead of legs and have up to two graduated scales. Vernier, dial and digital callipers give direct and accurate readings and are functionally identical, having a calibrated scale with a fixed jaw and another jaw with a movable pointer that slides along the scale. The Vernier calliper has a scale sliding parallel to the main scale for an additional, fractional reading to improve measurement precision.