Measurment of Pitch:

     A pitch value a screw thread can be measured in so many ways like by using screw pitch gauges, screw plug gauges and also by Tool Maker's Microscope. The screw pitch gauges are provided in a form of number of blades. Each blade provided with different thread profiles having different pitch values. The pitch value of each thread profile is mentioned on the blade. After manufacturing desired threads, the pitch value is checked by matching the profile with the number of pitch gauges.  

Screw pitch gauges

     A pitch value of external threads can also be determined by using Tool Maker's Microscope. In this method the pitch value can be measured by using two micrometers provided in longitudinal and traverse direction. By using the same cross mark, we should place the cross mark on any crest point or root point and then we should move that cross mark to the successive crest or root point by using the longitudinal micrometer. In between these two positions we should take micrometer readings as initial and final reading. The difference between these two readings is the desired pitch value.

Using a Pitch measuring machine:
     A pitch measuring machine consists of two vertical slides provided with two screws. These two screws are provided for fixing a threaded component. It means we have to adjust the component in between the two screws of slides. These slides be sliding on the guide of base of this machine. This machine is also consisting of an indicator provided with stylus. According to the movement of the stylus the reading on the indicator will be changing. This indicator is provided on a guide way which will be sliding in traversing direction. Here one of the sliding is provided with a micrometer head.

     After adjusting the threaded component in between the screws, we should insert the stylus of indicator in the thread and we should make the reading on indicator as zero. Then we should rotate micrometer so that the thread component moves in longitudinal direction. So, the reading on indicator changes. We should move the component until the reading again becomes zero. It means the stylus moved from a point on a flank surface to the next successive point on the next flank surface. Here, in between these two positions we should take two micrometer readings. The difference between two micrometer readings is the desired pitch value.