Lettering is the process of forming letters, numerals, and other characters used in technical drawing. There are three main methods of lettering: freehand lettering done without tools, mechanical lettering done with tools like guides and templates, and modern drawing done with computer-aided software. The dimensions of letters are defined by their nominal size based on the height of uppercase letters, their center line which runs through the middle of each line element, and their lettering angle which can be vertical or inclined up to 75 degrees.

1. LETTERING

2. LETTERING
• It is the process of forming letters,
numerals, and other characters used in
technical drawing

3. METHODS OF LETTERING
• Freehand Lettering
• Mechanical Lettering
• Modern Drawing

4. FREEHAND LETTERING
• It is done without the assistance of tools
• Vertical capital letters are preferred for
most technical work. They performed
within a 6x6 grid

5. MECHANICAL LETTERING
• It is done with the aid of tools, such as
lettering guides, templates, etc.

6. MODERN DRAWING
• It is a type of lettering that was done
with the computer-aided software

7. DIMENSIONS OF LETTERS
• Nominal Size – defined by the height
(h) of the outline contour of the upper-
case (capital)

8. DIMENSIONS OF LETTERS
• Center Line – It is the imaginary line in
the middle of each line or line element
which is a constitutive part of a graphic
character set

9. DIMENSIONS OF LETTERS
• Lettering Angle – The letter may be
vertical (upright) or inclined (sloped) to
the right from 75 degrees horizontal