- Coordinates for 3D CAD Modeling
- Geometric Entities
- 4.1 Manually Bisecting a Line or Circular Arc
- 4.2 Drawing Tangents to Two Circles
- 4.3 Drawing an Arc Tangent to a Line or Arc and Through a Point
- 4.4 Bisecting an Angle
- 4.5 Drawing a Line through a Point and Parallel to a Line
- 4.6 Drawing a Triangle with Sides Given
- 4.7 Drawing a Right Triangle with Hypotenuse and One Side Given
- 4.8 Laying Out an Angle
- 4.9 Drawing an Equilateral Triangle
- 4.10 Polygons
- 4.11 Drawing a Regular Pentagon
- 4.12 Drawing a Hexagon
- 4.13 Ellipses
- 4.14 Spline Curves
- 4.15 Geometric Relationships
- 4.16 Solid Primitives
- 4.17 Recognizing Symmetry
- 4.18 Extruded Forms
- 4.19 Revolved Forms
- 4.20 Irregular Surfaces
- 4.21 User Coordinate Systems
- 4.22 Transformations
- Key Words
- Chapter Summary
- Skills Summary
- Review Questions
- Chapter Exercises

## 4.12 Drawing a Hexagon

Each side of a hexagon is equal to the radius of the circumscribed circle (Figure 4.36a). To use a compass or dividers, use the radius of the circle to mark the six points of the hexagon around the circle. Connect the points with straight lines. Check your accuracy by making sure the opposite sides of the hexagon are parallel.

**4.36** Drawing a Hexagon

**Centerline Variation** Draw vertical and horizontal centerlines (Figure 4.36b). With *A* and *B* as centers and radius equal to that of the circle, draw arcs to intersect the circle at *C, D, E*, and *F*, and complete the hexagon as shown.

Hexagons, especially when drawn to create bolt heads, are usually dimensioned by the distance across the flat sides (not across the corners). When creating a hexagon using CAD, it is typical to draw it as circumscribed about a circle, so that the circle diameter is defining the distance across the flat sides of the hexagon (see Figure 4.32).

**4.37** Across Flats vs. Across Corners