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Old April 29, 2012, 07:40 PM   #26
SteelSlicer
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Join Date: April 26, 2011
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I've been a machinist for 25 years. Even though digital calipers may have 4 (or even 5) digits on the display, they are considered accurate to +/- .001" just like dial calipers. I prefer a good quality dial caliper, such as Starrett, Brown & Sharpe or Mitutoyo. Verniers have less problems than dial calipers, but I find them harder to read, and when you use them constantly, you end up taking a lot more time just reading the measurements. As far as readability for old eyes, I always make sure the dial is .100" per full revolution. There are some that are .200" per rev, with a .100 mark at the top & bottom of the dial. Even when I was young and could see I didn't like that. The divisions are so close together they're just plain hard to read. So if you need to be more accurate than +/- .001", you have to use a micrometer, and even then, it has to have the .0001" vernier on it, or else it's only good to .001". If you are checking the same bore repeatedly, pin gages are definitely more accurate, the lowest class (Class ZZ) have a +/- .0002" tolerance on the small diameters (.010" - .825").
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Old April 30, 2012, 09:27 AM   #27
WV_gunner
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I am a mechanic and automotive enthusiast. For micrometers, use regular micrometers that read to .0000, nothing less. They are not hard to read at all, they are extremely simple. If you have a hard time reading them, then I seriously doubt you can perform the work you want to. I have set of Mitutoyo set and paid around $100 used.
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Old May 2, 2012, 03:27 PM   #28
brickeyee
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Quote:
temperature drift in the electronics
Not much of an issue in the past 5+ years.

Ratiometric circuits do not depend on absolute value, but the ration between two values.

It makes things a lot easier.

Last edited by brickeyee; May 3, 2012 at 02:21 PM.
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Old May 2, 2012, 03:50 PM   #29
Strafer Gott
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Calipers make better thinking sticks. Their best use is for roughing out.
I know an old Smith employee that swears (Navy style) that micrometers are the only appropriate metrology tools. Starret makes electronic readouts that
read much smaller than.0001 inches, traceable standards, repeatable to Johannsen blocks, for about a grand.
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Old May 3, 2012, 06:17 PM   #30
RobertInIowa
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I use a digital mitutoyo. Excellent resolution, fast read, accurate, repeatable and not that expensive. I've never tried the dial ones.
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Old July 4, 2012, 05:19 PM   #31
4T4MAG
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Would there be any difference in accuracy between

Starrett Electronic
http://www.brownells.com/.aspx/pid=4...tronic-Caliper

Mitutoyo dial
http://www.brownells.com/.aspx/pid=3...-dial-calipers

Or $45 set of Lyman Dial or digital calipers?
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Old July 4, 2012, 08:27 PM   #32
ScottRiqui
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Just looking at the advertised accuracy for the Mitutoyo and Starrett you linked to, and for the Lyman digital and dial calipers I could find, they're all advertised to be accurate to 0.001", except for the Starrett which advertises 0.0005".
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Old July 5, 2012, 08:57 AM   #33
rgrundy
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I like the dial calipers but as with any tool buy quality and you'll never go wrong. Get a set of gage blocks to periodically check the accuracy unless you work in a shop that recalibrates them for you. You can send them to a company that does calibration if you wish also. The biggest difference between the two is that one uses an embedded tape to transfer data to the digital readout and the dial ones have a rack and pinion that mechanically drives the dial. The most common problems I see are that the electric ones sometimes lose the battery cover and the dial ones get dirty and sometimes jump the gears and need to be reset.

Last edited by rgrundy; July 5, 2012 at 09:03 AM.
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Old July 15, 2012, 02:53 PM   #34
wyop
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In order of what I prefer:

Vernier: There's nothing to gum up, they maintain their accuracy unless someone screws up the jaws.

Dial: They're what I'm used to, they're fast, reasonably accurate with skill and there's no batteries.

Digital: They're OK in their own way, but I only tolerate the high-end ones that are coolant/water proof and have batteries I can readily find. My biggest beef with many digital calipers is that they present false precision to the operator.

By all means, get a set of gage blocks for reference.
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