# Reading and interpretation of micrometer in thousandth of millimeter

## Use of the instrument of measurement 'micrometer' in the metric system and milesimal resolution: reading and interpretation

This text will aproach exclusivilly the interpretation of the milesimal part of the micrometer. If you still are not familiar with the utilization, reading and interpretation of the centesimal portion of the micrometer, interact with this page before you move on.

This text assume that you are familiar with the nomenclature of the components of the Micrometer <- if necessary, repassing click here and with the reading of ruler or line gauge, in millimeter <- repass by clicking here.

## Operation of the milesimal micrometer

figure 1 - thimble in partial cut to reveal the vernier that divide the centesimal part of the millimeter by ten

The main difference of this configuration is that this one has ten pararel lines to the 'basis line' graved in the shealth. Other difference occurs in the position of the marks of the half millimeter - figure 1.

## The resolution of the thhousandth micrometer, the reading of the vernier.

In the centesimal micrometer, the resolution was obtained dividing the thread pitch of the micrometreic fuse by the number of divisions of the thimble (Resolution = thread pitch of the micrometric fuse / number of the thimble divisions) or Tesolution = 0.5mm / 50 = 0.01mm.

On this thousandth micrometer the smallest difference between indications is divided by ten by a vernier engraved in the shealth. this way, the resolution will be: Resolution = 0.01mm / 10 = 0.001mm.

## Reading of micrometer in thousandth millimeter

To determine the value of the measure, it is necessary to sum:

• the value read in the scale engraved in the shealth, in millimeter
• represented by ( o ) 'in green color' in the animation below
• with 0.500mm in case the counter of half millimeter it is exposed
• represented by ( o ) 'in blue color'
• with the value of the thimble aligned with the 'refference line', in centesimal millimeter
• represented by ( o ) 'in orange color'
• with the value read in the vernier, aligned in the thimble, in thousandth millimeter
• represented by ( o ) 'in red color'

animation 1 - reading of the measure by the sum of the parcels

Tips
- click in the icon in the inferior corner of the animation 1 screen to alternate the value of the measurement
- use the icon 'eye'to hide the total and partial values
- with the 'closed eye', click in the colored circles to show the partial value related to themselves