A scaled drawing is one where an object that is being drawn is large or the object to be represented in the drawing is such a size that it’s impossible to draw full size on a sheet that can be conveniently handled in the shop where a part is being fabricated. In such cases, the drawing is made at a reduced scale, and is called a scaled drawing.
The text book definition is: “A scaled drawing is one in which the length of all the lines of the drawing bears a definite ratio to the length of the corresponding lines of the object. Thus, in a drawing made one-half size, each line of the drawing will be one-half the length of the corresponding line of the object.”
Say for instance you are creating fabrication drawings for a dumpster. If you draw this to full scale, the paper would have to be in excess of ten feet tall by sixteen feet long. This would be a hard drawing to drag around a welding shop, so we would reduce it to one eight it’s size on the paper. Once reduced, it would fit on a two foot tall by three foot long sheet of paper. A note or label would then be placed on the drawing that says 1/8″ = 1″ (one eighth inch equals one inch) so that it can be measured using a scaled ruler.
With this type of scaling, more than one view of the item we are drawing can be placed on a sheet like the front, rear, side or sides, bottom, top, and even an angled view called an isometric view.
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