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Old 2008-10-01, 11:53 AM   #40
sperry
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Real Name: Scott
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Quote:
Originally Posted by knucklesplitter View Post
An instrument can be repeatable within 0.1mm but only accurate to 0.2mm (or worse). When comparing 2 parts that have the same nominal dimension an instrument is more accurate/useful then if it has to measure something to an absolute accuracy of the same magnitude. In other words that caliper prolly can tell the difference between a part that is 25.0mm and one that is 25.1mm, but you cannot rely on it measuring something 150.0mm accurately within less than 0.2mm. Does that make sense?
No, I get the difference between accuracy and repeatability.

But for a set of calipers, where accuracy is usually the desired trait, why does the display have a .1mm resolution if the instrument is only accurate to .2mm? Shouldn't the last digit always be a multiple of .2mm to give the most accurate measurements?
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