Define "vernier"

"Vernier" is the name of the Frenchman who invented the scale around

1860.

"Caliper" is ambiguous, so I think Vernier is somewhat the generic term by default. Many metalworking terms are the result of long custom and are imprecise, even "iron". I wasn't sure what an "engine lathe" was until reading Joshua Rose's definition of it as a lathe with self-acting power feed, versus one with an X-Y slide rest that clamps to the bed as on a watchmakers' lathe.

jsw

I'd think that "dial caliper" or "digital caliper" would be more generic than "Vernier caliper". If I saw "Vernier caliper" I would think "I'm too lazy for one of those -- and besides, I always read them wrong". "dial caliper" and "digital caliper", OTOH, each mean something specific to me.

There might have been a reason why he "quit machining seven years ago".

i

I think that if you have a machinist who dates back to the days when calipers were either spring and firm joint or true vernier calipers, and who does not know that "vernier" defines the type of reading system, not the shape of the instrument (even though he may know how to read them), when the dial calipers, and then the digital ones came out, he called them by the same name he used for other tools of the same basic shape.

But it is certainly not acceptable to *me*, whether it is to him or not.

Then -- there are those who call the calipers of all reading styles "very nears", which may be a more accurate term when comparing them to micrometers. :-)

Enjoy, DoN.

Over the years, "vernier" has become short-term slang for "vernier caliper." It's not a good habit for the reasons posted by others.

I worked for a company run by three machinists, all trained post WWII in Germany.

All dial calipers, digital calipers and vernier calipers were called verniers.

I didn't use the term that way, but I knew what they meant.

David

Ed Huntress fired this volley in news: snipped-for-privacy@4ax.com:

Yeah... well, I _have_ a couple of verier calipers, and generally much prefer a dial version. It's not that I can't measure with a vernier scale, but as someone already said, "I'm too lazy...".

LLoyd

I haven't owned a dial caliper for many years, but it's the quickest to read, IMO. I acquired some digitals when I wrote and did photography for Mitutoyo. They'd give me some tools to photograph, and when I tried to return them, they'd say, "Oh, no, we've already written them off as advertising expense. Keep them." The ceramic gage blocks are nice. d8-)))

I do use my Swiss vernier caliper. I rely on its accuracy, but it would be too slow to handle if I were doing commercial work.

However, like a lot of old-time hobbyists, I don't use any measuring calipers very much. I use spring calipers a lot, and micrometers when I need that kind of accuracy.

Many machinists use the term vernier for sliding caliper. A digital caliper might look something like this:

Good grief. That's like having an electronic door-knocker. d8-)

I have a set of plastic calipers (several, actually, including one in the car) which use a vernier scale:

They aren't very accurate, but it is fun to use.

I remember when I was in chemistry class years ago we had a barometer with a vernier scale, and we were taught how to read the scale and record the barometric pressure before we would do our lab coursework.

Jon

You mean a doorbell? There are plenty of situations (like measuring wall thickness of castings) where you can't extract the caliper to measure the gap without changing the gap.

No, I meant an electronic door-knocker. A digital indicator with a data port for SPC is more like a doorbell. That at least makes sense. d8-)

That's what transfer calipers are for. That problem was solved over

100 years ago.

I don't doubt that the digital calipers can *theoretically* produce a more accurate measurement. But the tips and the general usage of legged calipers are not good for high-accuracy applications, anyway. They probably give a false sense of accuracy.

The point is not so much accuracy as speed. At best the tolerance for metal thickness on castings is going to be no less than 0.01"

-jim

Ok, I can see that.

To some extent, I'm just pulling your chain. Federal doesn't make toys; I'm sure they had a demand for it before they made it. They're not often out front with novel gadgets, either.

It's just a little ironic. Legged calipers don't have a lot of uses in commercial machining today. If you use them to make a numerical, dimensional measurement, it takes time and skill. It's difficult for two users to come even close to the same measurement, even if an individual user can get consistent results.

They're still of good use to hobbyists because they're good for measuring relative dimensions, comparing one part with another, and for transferring outside and outside measurements -- again, assuming the user has some skill. A skilled user can use them to detect a couple of tenths variation along a turned shaft; transferring that to an inside mike for reading the measurement value is another matter.

So a digital version may produce better consistency between users, and it's easier, of course, to get a numerical value. I wonder what kind of digital scale they're using inside. The lever arm has to be very large.

(raises hand!) I must have 15 pairs, including some hermaphrodite types.

It's probably mostly us hobbyists and maybe some repair shops. If the fit of two parts matters and the absolute dimension doesn't matter much, they can be great.

Interesting that it offers 0.05mm on the metric side, but fractional (1/128th") on the inches side -- like the old machinists used. (I've seen them in reprints of old catalogs, but all that I have seen and/or used were decimal inch and similar metric. No provisions for zeroing it, however.

I've personally thought it a step backwards when digital calipers started offering fractional readings as well as decimal ones.

Interesting. How much chemistry work is atmospheric pressure dependent? I could picture some things being pressure sensitive, but most chem class stuff would not be.

Enjoy, DoN.

"DoN. Nichols" fired this volley in news: snipped-for-privacy@Katana.d-and-d.com:

If you mean things like titration, no. But chemical reactions increase in rate with temperature and pressure.

Most industrial chemistry is highly dependent upon both.

Lloyd

"DoN. Nichols" wrote >

Boiling points, as in distillation.

jsw