Basic Woodworking

WOODWORKING

Chapter 8

Line Types and Quality

Introduction:

With technical drawings, much attention is given to line types and quality. These two important features

provide for an easy-to-read and easy-to-follow drafting standard.

Line types:

The type of line used in a technical drawing is important. Below is a description and example of each line type:

Object Lines Heavy, Dark Solid Line

When a person looks at a drawing the first thing they should see is the object, or the item to be built. This is

accomplished by using heavy dark solid lines. All other lines will be thinner and lighter than the object line.

Dimension and Extension Lines Thin, Light Solid Line

Dimension lines inform the viewer the size of objects. Because the object should stand out more than any

other line, dimension lines should not be close to the object lines. They should be at least one inch away. A

dimension line has two elements, the extension line and the dimension line. The extension line is drawn

perpendicular from the object for which the measurement will be noted. The dimension line is drawn parallel

to the object reaching to each extension line with an arrow head. On the dimension line, the measurement is

noted, looking something like this:

Center Lines Thin, Light Broken Line

Center lines are drawn to show the center point of a circle or an

arch. It is drawn the same thickness and weight of a dimension

line, only with small breaks towards the end of the line. When

showing the location of a circle or an arch, the center line will

always extend to the center point of the circle, symbolized with a

small cross. This tells the manufacturer the exact location to place

the center of the drill bit.

8”

5”

3/4”

9”

Drafting