Descriptive Geometry (Addaline)

Descriptive Geometry is rotating surfaces in order to find....

• True Size/Shape/Lenth/ and Angle
• Intersection points
• Distances

True Length Lines

If a line is parallel to a fold line in one view, it is true length in the next view

Point View

1. Find a true length line
2. Create a fold line perpendicular to the True Length line

True Size Surfaces

1. You must find true length of a line
2. Find point view of a line
3. Create a fold line parallel to edge view

-Addaline-

1. From a point, draw a line parallel to the fold line that intersects a surface of the same view
2. Once there is an intersection on the edge view of a surface, extend that line up into then next view so it intersect the same edge view in the other view
3. From that point in the second view, extend the line to the point in the second view from the point that started the line in the first view
4. That line that connects a point to an edge view in the second view is True Length, you can now make TSS and point view from there