Fractional digital caliper question
#16
(12-16-2021, 10:45 PM)Pirate Wrote: When I read my fractional, dial caliper, graduated in1/64 of an inch, it might read 1/64 and a little bit, like 2/3 the way to 2/64. I call it 1/64 and 2/3
How would a digital fractional caliper read this measurement?
Thanks. Sorry if a digital caliper is considered a power tool!

Digital isn't always better. With an analog dial caliper you know if you're close by the position of the needle in relation to the marks on the dial. 1/64" = .015625" and a digital caliper reading in fractions will round up or down by half that amount, .008" in the real world. That's not much, but if you're using calipers it's likely more that what's acceptable.
Bob Lang
ReadWatchDo.com
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#17
(12-23-2021, 04:24 PM)Bob Lang Wrote: Digital isn't always better. With an analog dial caliper you know if you're close by the position of the needle in relation to the marks on the dial. 1/64" = .015625" and a digital caliper reading in fractions will round up or down by half that amount, .008" in the real world. That's not much, but if you're using calipers it's likely more that what's acceptable.

You explained that much better than I was able to.
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#18
(12-23-2021, 04:24 PM)Bob Lang Wrote: Digital isn't always better. With an analog dial caliper you know if you're close by the position of the needle in relation to the marks on the dial. 1/64" = .015625" and a digital caliper reading in fractions will round up or down by half that amount, .008" in the real world. That's not much, but if you're using calipers it's likely more that what's acceptable.

That is only true if the digital caliper only reads in fractions, which may exist, but I have not seen those, of course I have not looked for them.  Most (in my limited experience, it is all that I have seen) "Fractional" digital calipers also read in decimal, so you eliminate the need for rounding up or down, you can get an exact reading (to within .001" even if the caliper will read to within a .0005", it's not really that accurate).  I prefer to get an exact measurement and convert to a fraction myself, as I believe I mentioned earlier in the thread.  If you need anything more accurate than 1/64", then you really should be reading the decimal scale anyway, IMHO.  

Where digital calipers shine, though, is on the fly conversion from inch to mm (and vise versa) for those times you're not sure what system of measurements your part was made to, or if you have an oddball part or not expecting something to be in one system of measurement (i.e. like the flats on the arbor of my 1950's USA built, DeWalt MBF being 14mm apart, sort of DeWalt's early DRM so that  you have to buy their arbor wrench back when metric wrenches were not common in the USA).
Paul
They were right, I SHOULDN'T have tried it at home!
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#19
Oh, my! That Starrett makes me salivate.
Carolyn

Trip Blog for Twelve Countries:   [url=http://www.woodworkingtraveler.wordpress.com[/url]

"It's good to know, but it's better to understand."  Auze Jackson
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#20
(01-02-2022, 04:11 PM)MsNomer Wrote: Oh, my! That Starrett makes me salivate.

Me too! But my $30.00 iGaging fractional caliper I've had for 20 years still works just fine. I do like that Starrett, though.
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