A good sketch of an object is one that you can use as a blueprint to manufacture the object. Your sketch must show all the necessary dimensions of the part, locate any features it may have (such as holes and slots), give information on the material it is to be made from, and if necessary, stipulate the processes to be used in the manufacture of the object.
Three principles of dimensioning must be followed:
- Do not leave any size, shape, or material in doubt.
- To avoid confusion and the possibility of error, no dimension should be repeated twice on any sketch or drawing.
- Dimensions and notations must be placed on the sketch where they can be clearly and easily read.
Consider Figure 14 and note whether these three dimensioning principles have been followed.