Do you get drawings that were originally drawn to scale, but because the drawing has been reduced in a photocopier or fax, the drawings are at an odd scale?
Do you get drawings in a metric or imperial scale and you don't have the correct scale ruler available?
Scale-Ruler simply requires you to enter a dimension length on the drawing and the actual length of the dimension line. Then Scale-Ruler will calculate the precise scale of the drawing and create a Scale-Ruler for you at that exact scale.
Simply print the Scale-Ruler, fold back the paper, and start taking measurements.