Do you know, that… ?

When you select Helisa / Spiral You can use the mode variable pitch to create a spring, in which the first roll (or more) It has a different stroke.

Here is an example of a ballpoint pen springs. In this example, the first few and last turns have a pitch equal to the thickness of wire.

In this case you can control the height and jump, height and a turn or jump and marketing. Depending on the choice always one parameter is read-only (column is gray).

A similar situation occurs when drawing spring amortization, used vehicles. The key is to choose the value of turnover at a stroke, diameter profile, because there may be infiltration. Ie from zero to 1.3 rotation jump is zero and smoothly passes in 50mm stroke – for the next 5 complete revolutions.

Comparison of the spring with zero pitch (on the left) and a spring constant pitch (on the right) presents the image below.