The micrometer is a precision measuring instrument in the decimal 3 position of millimeter, micrometer work by the movement of the screw.
Parts of a micrometer
A frame the u-shaped frame is designed to be rigid and stable.
B spindle a metal surface used for hold the object
C Sleeve scale the scale on the sleeve of the micrometer is the instrument's primary measuring scale.
D thimble scale a scale is moving by rotating the Thimble E
E Thimble Use rotated distance of spindle face B For a suitable size of object to be measured
F Ratchet is moved by turning the spindle B until the object is ‘trapped’ between these two surfaces and the ratchet makes a ‘clicking’ noise
G Lock nut is provided for locking Thimble E and Ratchet F and thimble D it on lock
How to use micrometer
Rotation the Thimble E until the spindle B Hold the object to be measured is placed between the anvil and the spindle B and spin the ratchet F is turned clockwise until the object is ‘trapped’ between these two surfaces and the ratchet makes a ‘clicking’ noise then Set the thimble lock G This means that the ratchet cannot be tightened anymore and the measurement can be read.