The modification of 3D models - Introduction to AutoCAD 2011: 2D and 3D Design - page 285

Fig. 14.29 The Helix tool in the Home/Draw panel

Specify top radius or [Diameter]: enter 35
Specify helix height or [Axis endpoint/Turns/turn
Height/tWist]: enter 100
Command:

Fig. 14.30 shows the sequence of DYN tooltips and the completed helix.

Fig. 14.30 Constructing the helix for the second example with the aid of DYN