Does 1 micron really make a difference? Many of our customers are delighted to use our precision engineering products. But why is accuracy so important? The difference between "accuracy" and "resolution" is often misunderstood.
Does an accurate measuring instrument mean it has good resolution? Quite likely.
Does a measuring instrument with high resolution mean it has good accuracy? Maybe.
There are no definite answers to this and the difference rests heavily on the quality of production during the creation of the measuring instruments.
Resolution
Resolution refers to the digit accuracy you can see on the product. Lets try the following pictures to see if you get them right!
What is the resolution of this digital caliper? Do you know?
What about the resolution of this digital micrometer?
Lets see if you got them right:
Hint: The answers come from looking at the number of digits after the decimal place.
The digital caliper above has a resolution of 0.01mm
The digital micrometer has a resolution of 0.001mm
We hope you got that right!
Here's a bonus question for you: does this mean that the digital micrometer is 10 times more accurate than the digital caliper?
Many would say yes. But the fact is - it depends, and very likely the answer will be no.
Accuracy
Accuracy takes into account tolerances specified by laboratory tests - these are often provided by the manufacturer. Any company can put a resolution of 0.01, or 0.001mm - but this does not mean the product performs to that specification.
Accuracy determines the tolerance of the product.
Here is an example - with a digital level measuring the accuracy of a cutting plate.
You may have a resolution of 0.01 degree in this case on the device.
But the important thing is to know what the tolerance is over longer distances. Imagine a plate that stretches for 5 kilometers: even a 0.01 degree difference will see a large difference from tip to tip.
This is unacceptable in most precision engineering situations.
You need to know what the mm/M reading is , and what accuracy is acceptable for your work.
Selecting a tool
Therefore: there are two distinct considerations when selecting a tool
- Application requirements
- What is the tolerance acceptable for this application
- Understanding the actual device
- What is the manufacturer's tolerance specifications for accuracy. Usually this is indicated seperately
- Do a calibration to ensure precision
If you need further assistance in this regard - feel free to reach out to us by phone or email.