Thread: Vernier Calliper vs Micrometer

Does a Digital Vernier Calliper surpass the need for a Micrometer?

I noticed that Mitutoyo micrometers are accurate to 0.01mm and that digital verniers are claiming +/- 0.02mm. However I am sure Mitutoyo products are better made than the majority of available digital callipers which all seem to look scarily alike despite brand or price.


I have a box load of imperial callipers, unfortunately I'm metric schooled.

In a word......NO.

The problem with calipers is the the big lump of meat hanging off them can influence the results. Because they have no way of regulating the measuring force used it depends on how hard you push on the jaws as to the measurement you get. Micrometers on the other hand have a ratchet or friction thimble that gives you the same measuring force every time.
Just beacause a digital caliper has a resolution of .005mm (my mity does) does not mean it is accurate to that. It does however trick you into thinking it does because the number is there in front of you to see.

Ew

I think there is also a difference in accuracy to resolution and these figures may be tandied about to confuse the buyer.

Interesting article here:
http://mikes-models.com/blog/index.p...d-micrometers/


Might have to see if I can get a good used metric mic on ebay at a reasonable price. Although it might open up a whole world of inaccuracy in my ability and machine set up

Mics seem to come with different tips, are flat or point preferred or is it determined purely by what you want to measure?

How do you date a mic?



All Mitutoyo all 0-25mm, 0.01mm all same price used.

I'm leaning towards the one from the drawing office (centre)

Just be nice to it and take it to a nice bar.

The main downside of any caliper measuring device is that you can easily measure off 90 degrees - that is, the jaws/ knife edges can easily tilt from true 90 degrees. This will give an incorrect/ larger measurement.

As a micrometer has flat jaw faces it eliminates this error when used correctly.

Rob

Originally Posted by DSEL74

How do you date a mic?



All Mitutoyo all 0-25mm, 0.01mm all same price used.

I'm leaning towards the one from the drawing office (centre)

the blue one i think is the most modern model.
flat anvils is the most popular for general work.
for measuring the wall thickness of pipe or bearings
the fixed anvil is rounded

I saw one of the blue ones advertised as the economy model…Is there different grades all show same specs.

Originally Posted by DSEL74

I saw one of the blue ones advertised as the economy model…Is there different grades all show same specs.

im not shore ive got one that looks the same 0-25mm
ill compare it to other ones i have.
aaron

Hi Dale,

You need both. The biggest advantage of the calipers, is the huge range, 0 - 150 mm and often more. Whereas Micrometers are limited in range..
To cover the same range as a caliper you'd need a number of micrometers.

The other advantages of calipers include the ability to do inside and outside measurements, not so easy with a micrometer.

But if you want to turn something to a particular fit that requires 0.01 or better accuracy, you won't get the precision with calipers, for all the reasons others have already mentioned.

You'll use calipers 10 times more often than the micrometer... but you still need both.

Ray

Originally Posted by RayG

Hi Dale,

You need both. The biggest advantage of the calipers, is the huge range, 0 - 150 mm and often more. Whereas Micrometers are limited in range..
To cover the same range as a caliper you'd need a number of micrometers.

The other advantages of calipers include the ability to do inside and outside measurements, not so easy with a micrometer.

But if you want to turn something to a particular fit that requires 0.01 or better accuracy, you won't get the precision with calipers, for all the reasons others have already mentioned.

You'll use calipers 10 times more often than the micrometer... but you still need both.

Ray

I have several good vernier callipers, a good dial calliper, and a cheap digital one. Starting to think may be the digital one should go in the bin and default back to the dial calliper. So I'm on the hunt for a Metric Mic it seems in 0-25, and maybe a 25-50 or what ever the next step is. Seems Mitutoyo and Moore & Wright metrics go for around $25 Used and chinese ones $13 New inc postage. I still think the used ones are the way to go…..

Originally Posted by DSEL74

How do you date a mic?



All Mitutoyo all 0-25mm, 0.01mm all same price used.

I'm leaning towards the one from the drawing office (centre)

- The one with the black plastic handles is the standard model and has been around a long time (I bought mine 40+ Years ago)
- The Blue one top left is the barebone low cost model, and has also been around a long time. Its new price is about half that ofthe model above.
- The bottom model must be the oldest one, maybe 1950's?

Chris

If you want to see the range that Mitutoyo make, here is a link to the American branches catalogue. http://ecatalog.mitutoyo.com/Micrometers-C1066.aspx
You will see a bewildering range, with features to enhance particular measurement tasks, work environments, accuracy requirements and probably dozens of other special requirements as well. The blue one you pictured, is one of their base models, but is up to most measuring tasks within its measuring range that you would see in general industry, and perfectly adequate for general use. Do be aware that like Rolex watches, Mitutoyo have their admirers who copy them, and then offer to share their handywork.
Having said all that, there will be plenty of good ones on eBay, as well as abused examples, so personal inspection if possible is advised. Others here will be more qualified than me to advise you on this, but if I was after a 0 - 25mm mike say, I would check that it read 0 when in the closed position, and then with a standard, I would see if it read correctly at the dimension of that standard. Most likely 25mm in this case. If it doesn't read 0 when closed and with the anvil and spindle faces wiped clean, then I would ask the seller to adjust the zero setting till it was reading 0, and then test with a standard to see if accuracy was maintained along the measuring range. While a set of gauge blocks would be ideal, not many will have them available to us. Either ball or roller bearings, or bearing cups from reputable manufacturers like Timken, SKF and FAG amongst many others will make good alternative test pieces, as the measurements of these items is to high levels of accuracy and is also well documented in bearing catalogues.
Rob.

Originally Posted by cba_melbourne

- .

- The bottom model must be the oldest one, maybe 1950's?

Chris

I've got one the same as the bottom one, that I bought new. I think it's about 10 years old now.

Mitutoyo mikes are a pleasure to use.

Always gives me a good feeling rolling through the range - it's just so silky smooth, and accurate.

Nice.

Rob

Originally Posted by RayG

Hi Dale,

You need both. The biggest advantage of the calipers, is the huge range, 0 - 150 mm and often more. Whereas Micrometers are limited in range..
To cover the same range as a caliper you'd need a number of micrometers.

You're not wrong. My Mitutoyo mikes go to 12" in inch measurements and my metric mikes go to 100mm. Haven't needed a bigger metric mike yet.

I use verniers all the time for rough measurements say +/- 0.002" - they (and I on a good day) can do better but if I really need better, I use a mike. Got about 7 pairs of calipers I think - 3 Mitutoyo sets, 3 Chinese sets and a Kingchrome electronic digital one. That one is handy for the fast/rough inch/metric stuff. The Chinese ones get used all the time for measuring drill bit shanks etc etc and I really don't care much what happens to them. The Mits ones live with the lathes & mills.

I don't like electronic digital measuring gear. I have some but I don't like it. Other people are very happy with it so it's just a prejudice on my part.

Be aware that Mitutoyo electronic mikes seem to be commonly faked & sold on ebay. I'd be very careful buying them there.

PDW