Scales are made with different divisions for different purposes. For machine, structural and architectural drawing the architects’ scale of proportional feet and inches is used.
Thomas E. French and Carl L. Svensen Mechanical Drawing For High Schools (New York: McGraw-Hill Book Company, Inc. , 1919) 11
2400×192, 143.2 KiB
1024×81, 22.8 KiB
640×51, 11.7 KiB
320×25, 3.9 KiB