Various Types of Letters and Lettering Standard:

Here we denote the characteristics of lettering utilized on technical drawings, and associated documents. It concerns primarily the letters written along with the aid of stencils however is similarly applicable for free hand-lettering.

Dimensions

The height h of the capital letter is considered like the base of dimensioning. The two standard ratios for d/h equivalent to 1/14 and 1/10 are most economical like they conclude in a minimum number of line thicknesses, as like demonstrated. The recommended ratios for the height of lower case letters without tail or stem, for the space among characters, for the smallest space of the base lines and the smallest space of words are already specified.

Figure  Dimensions

          Lettering A (d = h/14)                                                                                  Values in Millimeters

[Note : The spacing a among two characters may be reduced via half if this provides a better visual effect, as in example LA, TV; it than equivalents the line thickness d.]