Engineering Drawing Changes

Drafting Menu

There are two common methods of indicating where a revision has changed a drawing that contains a system diagram. The first is the cloud method, where each change is enclosed by a hand-drawn cloud shape, as shown in the illustration below - left. The second method involves placing a circle (or triangle or other shape) with the revision number next to each effected portion of the drawing, as shown in the illustration below. The cloud method indicates changes from the most recent revision only, whereas the second method indicates all revisions to the drawing because all of the previous revision circles remain on the drawing.

The revision number and revision block are especially useful in researching the evolution of a specific system or component through the comparison of the various revisions.

Click on the above image to enlarge