TABLE OF CONTENTS The following information represents the standard methods and procedures used to prepare engineering drawings. [This section is taken from ANSI Y14.5M ?1994, Dimensioning and Tolerancing, by permission of the American Society of Mechanical Engineers.]
Dimensioning and tolerancing shall clearly define engineering intent and shall conform to the following:
Each dimension shall have a tolerance, except for those dimensions specifically identified as reference, maximum, minimum, or stock (commercial stock size). The tolerance may be applied directly to the dimension (or indirectly in the case of basic dimensions), indicated by a general note, or located in a supplementary block or the drawing format ANSI Y14.1.
Dimensioning and tolerancing shall be complete so there is full understanding of the characteristics of each feature. Neither scaling (measuring the size of a feature directly from an engineering drawing) nor assumption of a distance or size is permitted, except as follows: Undimensioned drawings, such as loft, printed wiring, templates, and master layouts prepared on stable material, are excluded, provided the necessary control dimensions are specified.
Each necessary dimension of an end product shall be shown. No more dimensions than those necessary for complete definition shall be given. The use of reference dimensions on a drawing should be minimized.
Dimensions shall be selected and arranged to suit the function and mating relationship of a part and shall not be subject to more than one interpretation.
The drawing should define a part without specifying manufacturing methods. Thus, for example, the...
