Part Modeling > Base Features > Volume Helical Sweeps > To Set the Pitch in Helical Sweeps and Volume Helical Sweeps
  
To Set the Pitch in Helical Sweeps and Volume Helical Sweeps
Pitch is the distance between the coils of a helix. The pitch can remain constant for the entire helix, or it can vary, with different distances between the coils at different places along the helix.
Constant Pitch
Variable Pitch
constant
variable
You set the varying pitch by defining pitch points. The first pitch point is always projected from the start of the helix profile onto the helix axis of revolution, and the last pitch point is projected from the end of the helix profile onto the helix axis of revolution.
You define the location of any pitch points between the first and last point along the helix axis of revolution. You can set the location using a reference, a ratio from the start point, or a real dimension (value) from the start point along the axis of revolution.
1. Pitch point 1 (helix profile start)
2. Pitch point 2 (helix profile end)
3. Pitch point 3
4. Pitch point 4
5. Pitch point 5
6. Helix profile
7. Axis of revolution
8. Section
9. Arrow on the helical profile indicates the start point of the helical sweep
To set the pitch, do one of the following:
Constant pitch:
Next to , enter a pitch value.
Variable pitch:
1. Click the Pitch tab. The start point of the helix profile is projected onto the axis of revolution, and is listed in row 1 of the table.
2. Click Add Pitch. The end point of the helix profile is projected onto the axis of revolution, and appears in row 2 of the table.
3. Add additional pitch points where you want to vary the pitch:
a. Click Add Pitch. A row is added to the table, and a point is added half the distance between the end point of the axis and the closest point to the end point.
b. Under Pitch, type or select a pitch value for the point.
c. Beginning with row 3, under Location Type, select the method by which pitch point placement is determined:
By Value—Sets point location using a distance value from the start point.
By Reference—Sets point location using a reference.
By Ratio—Sets point location using a ratio of the profile height along the axis of revolution from the start point.
d. Under Location, set the location for each point:
When By Value is selected, type a distance value from the start point.
When By Reference is selected, select a point, vertex, plane, or surface to set the pitch point location.
When By Ratio is selected, type a ratio of the profile height from the helix profile start point projected onto the axis of revolution.
e. To delete a pitch point, select its row in the table, and right-click and select Remove Pitch Point.
Back to To Create a Helical Sweep
Back to To Create a Volume Helical Sweep.