Shasi:
If you want to draw the helix around the Z-axis, the circle of radis 6mm must be either in the XZ plane or YZ plane. Remember that this circle will be swept along a spiral along the Z-axis. Next you have to move your circle to (r,0,0) if the circle is in the XZ plane or to ((0,r,0) if...
Make sure that the 2D cross section does not intersect the helix when it is swept across the spiral. For example if the 2D object is a circlular disk centered at the origin(0,0,0) and you want to sweep it across a spiral along the Y-direction you get self-intersection. You must move the disk to...