How to Read a Metric Vernier Caliper

Hi, I'm Bob weld

And this is how to read a metric vernier caliper there are different kinds of vernier scales designed to do different jobs

But they all work pretty much the same way today

We're going to look at a metric vernier designed to measure to the nearest 150th of a millimeter that is point zero two

Millimeters see how one divided by 50 equals point zero two

Now the first thing we're going to measure with our vernier caliper is nothing

That's right [will] measure zero it may sound [like] a silly thing to do

But we're going to do it for a couple of reasons. Let's do it, and you'll see what I mean

You see when the calipers are fully closed measuring zero width you can see the places where you can take measurements

These surfaces are where the two parts of the calipers line up?

You'll also notice there are gaps and a couple of places on the calipers these are not places to take measurements so don't mess up

By putting something in one of those gaps

Now with the calipers closed you can see where you're supposed to read the main scale

there are two scales on a vernier caliper the main scale and the vernier scale I'm

Going to erase the vernier scale and let you just look at the main scale first

You see the zero mark points to the place where you're supposed to read the main scale

Right now it points to zero do you see that good let's read the main scale first. [it's] super easy

I'll close the calipers on this work piece, and we'll see what the main scale says

These marks represent hole millimeters, so the reading is one two three four five five

Millimeters, just be sure to look at the zero mark and not at this part

That's a common mistake, and it will give you the wrong reading so the reading is five millimeters

That's pretty easy right before we move on to the vernier scale let me show you what it's going to tell us, okay?

Let's say when we looked at the main scale the reading wasn't right on the mark like it was last time

Let's say it looked like this

See how the mark is between five and six millimeters. It looks like it's a little beyond halfway

You see the vernier scale is going to tell us almost exactly how far over the mark is

Okay, you're ready to see the vernier scale

But I'm only going to draw the main part of it first now you see the marked number from zero to ten

Each of these marks represents a tenth of a millimeter they're going to tell us the tenth of a millimeter and here's how they work

Look carefully

And you [will] notice that one of the marks on the vernier scale lines up better with the main scale marks and the others

Which one looks like it lines up best to you? [I'll] zoom in and let you look

Let me show you a hint about where to look on the vernier scale to see where the marks line up

You see how our pointer was a little more than halfway between marks that means the vernier scale will line [up] a little past halfway

Now do you see the mark that lines up better than the rest?

It looks like the seven is lining up the seven means point seven millimeters

but this caliper can measure even more accurately than that I'll

Redraw all the marks and let you look again

Now see that the mark next to the seven lines up best, but what is the value of that mark?

Remember how this caliper had a label that said point zero two on it

That is what each mark is point zero two millimeters

Let's count up on the vernier scale to be sure we've got it this 6 would be 0.6

teen the next Mark point 62 then point six four point six six point six eight point seven zero

then point 72

The reading is five point seven two millimeters pretty neat, huh?

I'm going to let you try a few we're going to start off easy

I'm going to draw a caliber that only reads to the nearest tenth of a millimeter just to be sure you're with me

I'm going to show you the overall picture first then zoom in to let you see the vernier better, okay?

When you see [Sparkies] pause pause the video and write down what you think the reading is

The reading is sixteen point two millimeters. Let me step you through it

Just in case you missed something here are the hole millimeters from the main scale 10 11 12 13 14 15 16

okay, and

You see how the reading is just past 16 mark

so we'll look to the front of the vernier scale for where the marks line up and

There it is at the point to mark so the reading is sixteen point two milliliters. You got it, okay?

Let's go for broke and see if we can read the full point zero two millimeter resolution

Ready for this one again. I'll show the whole caliper then zoom in to let you see the vernier better here

We go pause the video and write down your answer

Now I know this is hard so before I give the answer I'm going to point to the place where the vernier lines up

Does that help take a minute and check your answer and be sure it's correct?

The reading is 19 point one six

[let's] try another one this time

[I] won't give any hints

But I will [zoom] way in so you can see the calipers really well if you get this one

You pretty much know what's going on

Pause the video and make sure you can read the whole millimeters

Did you say 12 millimeters, okay?

Let's do the hard part [and] read the vernier scale I'll zoom in and let you take a closer look

But first remember the trick see how the reading is Beyond halfway between the marks that

Means we need to look on the high side of the vernier scale. I'll fly the view down there and let you look here

We go pause the video look carefully

The mark that lines up best is here now. What number? Is [that] this is the point seven so

0.72 for

Six the answer is [12] point seven six

That's about all the time we have for now

Vernier calipers are hard to read, but with a little practice

I'm sure you'll be able to do it without too much trouble. I'm Bob weld and these are [weld] notes