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# Use of Vernier Scale in Fractional Inch – Measuring and Interpretating

`virtual vernier scale simulator for the reading and interpretation of the fractional inch 1/128"`

## How to use one vernier scale for the reading and interpretation of the fractional inch 1/128″

We saw in the topic: Use of measures in fractional inch – comprehending and measuring without that to read one ruler or line gauge with main scale in fractional inch it is not a mistery that most people imagine.

In the topic vernier scale: simulator of reading and interpretation in fractional inch resolution 1/128″ we saw how each division of the main scale represents 1/16 (one sixteen avos) of inch. We saw also that this space is divided by the vernier by eight and that the value of the measure is obtained by the sum of the integer, the fraction of the main scale is the fraction of the nonius. With the improvement brought by the practice, this sum becames automatic. However, the measurement value is obtained by adding the whole, the fraction of the main scale and the fraction of vernier. With the improvement brought by the practice, this algebra becomes automatic. All in all, we not always have time to perfect this whole thing.

I am gonna give you some tips.

We saw in the topic:

Virtual inch vernier caliper – simulator in 1/128″ fractional – metrology that the engeneering of the use of the vernier is in how to identify in which part of the distance between two marks (of 1/16″) the zero of the vernier is. For example: when the zero in the vernier is in the middle of the distance between ine mark and another, for example, we sum half of 1/16″ (1/16 * 1/2 = 1/32) to the measure of the main scale. The number 4 (that is half of 8) of the vernier aligned indicates this (if you didn’t understand anything is a signal that you must interact with the page above and later come back here)In the image beside, the fifth mark of the vernier indicate that we must sum 5/128 to the measure of the main scale.

We saw an easy way to create this reasoning, which is:

In the main scale, count the number of marks after the whole inch and before the zero of the vernier and multiply this value by 1/16 (7 marks * 1/16 = 7/16)

See how the mark of the vernier is aligned and multiply it by 1/128″ (5ª mark * 1/128 = 5/128)

Add these values to the whole of the main scale, (7/16 = 14/32 = 28/64 = 56/128 + 5/128 + 1 = 1.61/128)

Because 61 is an odd number, it is not possible to simplify.

All this algebra can, at the beggining, make someone bothered and afraid to make counts. There is an even simpler way to read these measures:

Each mark of the main scale is equal to 8/128″ (1/16 = 2/32 = 4/64 = 8/128 – see in the vernier one number 8 to help you remember) so:

In the main scale, count the number of marks after the whole inch and before the zero of the vernier multiply this value by 8/128 (7 marks * 8/128 = 56/128)

See which mark of the vernier is aligned and multiply by 1/128″ (5ª mark * 1/128 = 5/128)

Add these values with the whole of the main scale (56/128 + 5/128 + 1 = 1 61/128)
For even numerals simplify the fraction by dividing both the numerator and the denominator by two until the numerator becomes odd.

With the experience, go observing if the mark of the vernier that aligned is a pair number that we can simplify before starting the calculations, in order to facilitate the counts even more. Let’s supose that the fourth mark of the vernier was aligned in the previous figure, (we can infer that the result will be equal to the measure that we calculate minus 1/128) but let’s make it reading and interpretating it. Let’s go:

See which mark is aligned in the vernier and multiply by 1/128″
(4ª mark * 1/128 = 4/128)

Simplify this fraction: 4/128 = 2/64 = 1/32
(remember that is the half of 1/16″)

In the main scale, count the number of marks after the integer inch and before of the vernier and multiply this value by 2/32
(7 marks * 2/32 = 14/32)

Add these values to the whole of the main scale (1/32 + 14/32 + 1 = 1.15/32)

The figure 2 of the topic: vernier scale: simulator of reading and interpretation in fractional inch resolution 1/128″ demystifies the fraction and, in special, the denominator that the vernier shows.

The tip is: if the denominator is:

32: each mark of the main scale must be multiplied by 2/32

64: each mark of the main scale must be multiplied by 4/64

128: each mark of the main scale must be multiplied by 8/128

It is also good if you memorize this list.

## Simulator: Use of vernier caliper vernier scale in fractional inch. Comprehending and measuring resolution 1/128in

Observe that:

the fraction in red represent the value read in the each mark divides 1/16 by 8 = 1/128″

the fraction in black is the value read in the main scale, each mark is equal to 1/16′ or 8/128″

the integer in black represent the whole inches

the mixed fraction, in blue, is the sum of the indicated fraction by the with the indicated fraction in the main scale, to the whole inch indicated in the main scale, after the simplification

### That’s it.

##### Eduardo Stefanelli

Engenheiro por profissão, professor por vocação