# How to measure from vernier calliper

It's all too rare, here. The vernier scale is constructed so that it is spaced at a constant fraction of the fixed main scale.

The user then reads the finer vernier scale see diagramwhich measures between the smallest graduations on the fixed scale—providing much greater precision. The difference between the value of one Main scale division and the value of one Vernier scale division is known as least count of the Vernier. It is also known as Vernier constant. Let the measure of the smallest main scale reading, that is the distance between two consecutive graduations also called its pitch be S and the distance between two consecutive Vernier scale graduations be V such that the length of n-1 main scale divisions is equal to n Vernier scale divisions.

On decimal measuring instruments, as in the diagram below, the indicating scale has 10 graduations that cover the same length as 9 on the data scale. Note that the vernier's 10th graduation is omitted.

On an angular measurement instrument, the data scale might be in half-degrees, with an indicator scale that provides 30 1-minute graduations that span 29 of the half-degree graduations.

### How to Read a Vernier (caliper)

The vernier scale is constructed so that it is spaced at a constant fraction of the fixed main scale. So for a decimal measuring device each mark on the vernier is spaced nine tenths of those on the main scale. If you put the two scales together with zero points aligned, the first mark on the vernier scale is one tenth short of the first main scale mark, the second two tenths short, and so on up to the ninth mark—which is misaligned by nine tenths. Only when a full ten marks are counted is there alignment, because the tenth mark is ten tenths—a whole main scale unit short, and therefore aligns with the ninth mark on the main scale.

Now if you move the vernier by a small amount, say, one tenth of its fixed main scale, the only pair of marks that come into alignment are the first pair, since these were the only ones originally misaligned by one tenth. If we move it two tenths, the second pair aligns, from these are the only ones originally misaligned by that amount. If we move it five tenths, the fifth pair aligns—and so on. For any movement, only one pair of marks aligns and that pair shows the value between the marks on the fixed scale. Vernier scales work so well because most measure are especially how at detecting which of the lines is aligned and misaligned, and that ability gets better with practice, in fact far exceeding the optical capability of the eye.

This ability to detect alignment is called 'Vernier acuity'. Zero error is defined as the condition where a measuring instrument registers a reading when there should not be any reading.

In case of vernier calipers it occurs when a zero on main scale does not coincide with a zero on vernier scale. The one just below it is a thumb button. This is the proper way to hold a caliper. Use your vernier to slide the jaws open and closed.

### Vernier scale

Yup, another tool that was totally designed for righties. Use the locking screw at the top if you want to set a dimension on the caliper and then check parts against your setting.

So let's read a measurement off of the caliper.

## How To Read A Vernier Caliper

First, a quick math refresher. Whole numbers 1,2,3, etc. We are vernier to be working with the 3 places to the right of the measure point. A human hair is about 3 thousands of an inch 0. Other calipers can be much longer in length. The big number in the center of the scale is the inch number. Notice that each inch is divided into 10 equal parts with the numbers 1 through 9.

How also a scale on the bottom of the picture. It starts at zero, there's a 5, a 10 and a THAT, is the vernier part of the caliper. The 3 is to the left of the zero on the vernier, so we'll add that to our number 1. The zero line is to the right, of the second line after the 3. So there is at least fifty thousanths there 0.

Notice how the zero line is just a smidge to the right of that second line after the 3. Now look at the large 2 and notice that the vernier line of 13 is to the LEFT.

So the trick is to find which lines on the vernier lines up exactly with the scale on the center. In this case, it looks like It's 6 all right. NOT the 6 on the top scale - the 6 on the bottom vernier scale. So, we were up to 1. Add them all up and we have 1. Let's try another one. The zero on the vernier is to the left of the 1 whole inch mark Let's write that down 0.

Hmmm, the vernier zero line is almost at the number 7; there are 3 measures Let's look at the vernier scale and see what lines up to understand how much more. Let's get a better shot of that. It looks from That would be 0. Read, six hundred and ninty thousanths. Fantastic explanation, I how really understood how to vernier off the smaller figures, Now hows about a metric one for us Brits: I've never seen a vernier vernier caliper - only dial calipers.

Though I imagine that they do exist and that they would work relatively the same. I just got one from Home How, it has both metric and standard readings, though the standard looks to be in fractions, not decimals, so I have next to no clue how to read it properly.

The metric side, however, is easy to understand after your instructions converting them to fit the metric scale, of course. I just found an on-line vernier caliper tutorial with a simulator you can adjust by dragging the jaw with your mouse. You can write your reading on a piece of paper and then click "show" to learn what the correct reading is to a tenth of a millimeter. I tried to link it through the rich text editor here, but it would not work, so here is the URL: It's amazing how you guys like using the decimal point, but don't like using the decimal system!

Millimeters make it much easier. Back in the 70's when we tried to trade in all of our American system calipers for decimal system calipers, there was going to be a sixpence fee. There are 2 types of countries in this world.

Those that use the metric system and those that have put a man on the moon. Metric system is far simpler than Imperial system. You just move the decimal point forward or backwards to get you measurements. The measurement-reading technique described in this post will be similar for vernier calipers which output measurement readings in inches. In order to read the measurement readings from vernier caliper properly, you need to remember two things before we start.

For example, if a vernier caliper output a measurement reading of 2.

We will just use a two steps method to get the measurement reading from this:. In order to obtain the final measurement readingwe will add the main scale reading and vernier scale reading together.

This will give 2. Now, we shall try with zero error. If you are not familiar on how to handle zero error for vernier calipers, I suggest that you read up on Measurement of Length. The reading on the top is the measurement obtained and the reading at the bottom is the zero error. Find the actual measurement.

how to use a vernier caliperIf you do not understand the subtraction of the negative zero error from the measurement, please read on. Since the zero error is Hence, you will have to ADD 0. The subtraction is done in the above case is to have an elegant way of obtaining a resultant addition: