Poly carbonate digital calipers

I have a $10 harbour freight, It works ok but only has 1 decimal place for mm and 2 for inches. I keep it in my desk drawer for quick measurements. Don
 
I had a dial one in fractions for the cabinet shop. It was ok but the jaws wore even on wood. They list the accuracy as .008.

Greg
 
I have two Harbor Freight #47257 calipers that I bought 3-4 years ago. I use one every day for rough measuring in the shop, and it gets used on rusty stock, whatever needs a quick measure. The first one is still on its first battery, comes with a spare, and is still accurate to .001-.002", no issues. The second one is still new in the box. I bought them for $9.99 each, minus 25%, and including a freebie with each. I do not use them for work that needs to be accurate, more as an easier reading version of this:
th
 
Thanks Bob, good article.
Being a target shooter I am fully aware of the difference between accuracy and precision.
But it was interesting to read about cheater circuits in digital programming...

When I compare a good dial calliper to a cheap digital one, the digital shows consistently .003'' to .004'' more than the dial caliper at 3 inches.
I have more trust in the Mitutoyo dial caliper and enjoy it more anyway.
 
Do any of you have experience with plastic callipers like these or similar?
Check out the resolution of .0005''
http://www.kbctools.ca/products/MEASURING @@26 INSPECTION/CALIPERS/ELECTRONIC DIGITAL CALIPERS/5750.aspx

Or these
http://ftctools.com/polycarbonate-6-digital-caliper

How low can the price go?

Well how can it have a resolution of .0005 and an accuracy of only .008. Let's face it, there's something wrong with that. Those are at opposite ends of the accuracy /repeatability spectrum. The HF with res of .01 is probably about as accurate.
 
Well how can it have a resolution of .0005 and an accuracy of only .008. Let's face it, there's something wrong with that. Those are at opposite ends of the accuracy /repeatability spectrum. The HF with res of .01 is probably about as accurate.
Jeff, read the article in the link in my post above. Resolution, which sounds like a really cool and accurate thing, is only what the scales can show. If a ruler has 1/64th inch markings on one side and 1/8" markings on the other side, then the resolution of one side is 1/64" and the resolution of the other side is 1/8". If a caliper has digits on it that go down to .0001", then that is the resolution, even is the caliper is made of soft rubber. Repeatability is a completely different thing as well. If you keep closing that caliper to zero, but get different readings each time, then you have poor repeatability. All that stuff matters in getting good measurements, and more, such as ease of reading, and how comfortable the tool is to hold and use.
 
Look,you can have .0005 resolution. it means nothing if the accuracy is .008.
end of story. The unit is just .008... posting .0005 is a trap. what's the point of having that resolution if you only have .008 accuracy.
I don't need to read it... having .0005 on accuracy of .001 is fine, you are now +- .0005, having a resolution of .0005 on a .008 means you are now +- .004 since you can't rely on the accuracy of .001 to begin with...
Yes/No?
 
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