A helix is an open 2D or 3D spiral.
You can use a helix as a path along which to sweep an object to create an image. For example, you might sweep a circle along a helix path to create a solid model of a spring.
When you create a helix, you can specify the following:
If you specify the same value for both the base radius and the top radius, then a cylindrical helix is created. By default, the top radius is set to the same value as the base radius. You cannot specify 0 for both the base radius and top radius.
If you specify different values for the top radius and the base radius, then a conical helix is created.
If you specify a height value of 0, then a flat, 2D spiral is created.
A helix is a spline approximation of a real helix. Length values may not be completely accurate. However, when you use a helix as a sweep path, the resulting values will be accurate regardless of the approximation.