The dimensions have to be within the tolerances of a specified datum.
When surface datums are shown on extension lines, they are offset from dimension line arrows. Axis datums and center plane datums, on the other hand, can align with the dimension line's arrowheads.
To a certain extent, it is arbitrary. The designer chooses based on: -practicality of measuring from datums or origins -critical faces, surfaces, or dimensions -application. Sometimes, datums for a part are kept the same as the ones chosen for the overall assembly, especially if the design is a collaborative effort.
types of datums
Datum is singular. Data or datums is plural.
To a certain extent, it is arbitrary. The designer chooses based on: -practicality of measuring from datums or origins -critical faces, surfaces, or dimensions -application. Sometimes, datums for a part are kept the same as the ones chosen for the overall assembly, especially if the design is a collaborative effort.
you could say 'Jūs datums mani?' which means will you date me.
Jonathan Iliffe has written: 'Datums and map projections for remote sensing, GIS, and surveying'
Setting the work holding device in relation to the machine datums and reference points ensures accurate and consistent positioning of the workpiece. This helps to maintain precision during machining operations, reduces errors, and ensures that parts are consistently produced to the desired specifications. Proper alignment also minimizes the need for manual adjustments and rework, saving time and improving overall efficiency.
a theoretically exact point, axis, or plane derived from the true geometric counterpart of a specified datum feature. A datum is the origin from which the location or geometric characteristics of features of a part are established.
The noun 'datum' is a singular noun, a word for a piece of information or a basis for reasoning or a conclusion.The plural noun is 'data'.
Datum is the singular form of the word data in computer terminology. It also is defined as a set of values to define a specific geodetic system. The plural of this word, however, is datums.
The true singular form of data is "datum." However, it's so rarely used, that people just assume that "data" is singular form.