How to use a screw gauge in measurement?
Answers
Answer:
Measuring Procedure
1. Situate the item whose length, diameter or thickness is to be determined betwixt the rods (spindle and anvil).
2. Turn the thimble or ratchet to close the rods around the item to be measured. The rods should lightly touch the item betwixt them but not clamp down on it.
3. Flip the locking lever to lock the rods in place.
4. Read the value just exposed by the thimble on the central line of the cylinder. This value is in mm (millimeters). Typically, there is a mark every half-millimeter, with the mm marks rising above the central line and the half-millimeter marks going below it. For example, you might note that an object indicates 12.5 millimeters.
5. Read the mark on the thimble aligned with the central line on the cylinder. This mark is in hundredths of mm. For example, you might read the figure 12 on this scale, indicating a reading of 0.12 mm. There are 50 such marks, meaning that each turn of the thimble corresponds to half a mm, the distance betwixt the upward and downward marks on the cylinder central line.
6. Add these values together. This is the measurement of the item betwixt the rods. In the example, you would add 12.5 and 0.12 to get 12.62 millimeters.