hanermo
Titanium
- Joined
- Sep 28, 2009
- Location
- barcelona, spain
Great thread.
Imho it conflates the 2, like always tends to happen.
Accuracy is the ability to make, or measure, a part or feature of a part to an established standard, like a perfect inch or meter or whatever.
A perfectly accurate meter is the exact same length as the one in the museum (arts y metiers iirc)I visited 3 years ago in france.
Precision implies accuracy but does not guarantee it.
Precision is making a needle valve for an ic engine, or a lens for a home telescope.
The lens is probably precise in its curvature to about 0.05 microns, or 0.0005 mm, or 0.0000025".
But the lens, or valve, is not necessarily accurate, because it does not have an established size, measurement, radius, or curve profile.
They can have excellent fits, and fantastic resolution, and amateurs routinely fit stuff to better than 1 micron, often better than 0.1 micron in telescopes etc.
Precision is usually badly used.
It should be == accuracy, and resolution used for machine tool stuff.
Resolution is the min. size you can move, or make a feature like a divot, whatever.
If you can make a cut of 0.001 mm your machine tool has a resolution of 1 micron.
This does not mean that your machine tool can cut a piece to 10.001 mm - not at all.
Or that it can make 3 pieces with 0.001 mm ledges, of size 10.001 mm, for example.
Resolution is a better word than precision.
Accuracy is a good word. It says anyone anywhere can measure the piece and come up with a result that others can repeat if needed.
Most / many here could make flat ledges in steel of 0.001 mm feature size.
But they mostly would only moderately match ledges cut by someone else.
They would have precision and resolution, but would not be accurate to 0.001 mm levels.
Many here could also work the ledges to be generally accurate to 0.001 mm.
This would be specialist work, and a customer would pay a lot of money for it.
Imho it conflates the 2, like always tends to happen.
Accuracy is the ability to make, or measure, a part or feature of a part to an established standard, like a perfect inch or meter or whatever.
A perfectly accurate meter is the exact same length as the one in the museum (arts y metiers iirc)I visited 3 years ago in france.
Precision implies accuracy but does not guarantee it.
Precision is making a needle valve for an ic engine, or a lens for a home telescope.
The lens is probably precise in its curvature to about 0.05 microns, or 0.0005 mm, or 0.0000025".
But the lens, or valve, is not necessarily accurate, because it does not have an established size, measurement, radius, or curve profile.
They can have excellent fits, and fantastic resolution, and amateurs routinely fit stuff to better than 1 micron, often better than 0.1 micron in telescopes etc.
Precision is usually badly used.
It should be == accuracy, and resolution used for machine tool stuff.
Resolution is the min. size you can move, or make a feature like a divot, whatever.
If you can make a cut of 0.001 mm your machine tool has a resolution of 1 micron.
This does not mean that your machine tool can cut a piece to 10.001 mm - not at all.
Or that it can make 3 pieces with 0.001 mm ledges, of size 10.001 mm, for example.
Resolution is a better word than precision.
Accuracy is a good word. It says anyone anywhere can measure the piece and come up with a result that others can repeat if needed.
Most / many here could make flat ledges in steel of 0.001 mm feature size.
But they mostly would only moderately match ledges cut by someone else.
They would have precision and resolution, but would not be accurate to 0.001 mm levels.
Many here could also work the ledges to be generally accurate to 0.001 mm.
This would be specialist work, and a customer would pay a lot of money for it.