PartDesign AdditiveHelix

From FreeCAD Documentation

PartDesign AdditiveHelix

Menu location
Part Design → Create an additive feature → Additive helix
Default shortcut
Introduced in version
See also
PartDesign SubtractiveHelix


The AdditiveHelix tool creates a solid by sweeping a selected sketch or 2D object along a helix path.

The profile (B), is swept around axis (A) in order to produce the solid helix (C)


  1. Select the sketch to be swept into a helix. A face on the existing solid can alternatively be used.
  2. Press the PartDesign AdditiveHelix button.
  3. Set the Helix parameters (see next section).
  4. Inspect the Helix in the view window, to ensure that the parameters do not result in a self intersecting helix.
  5. Press OK.


When creating an Additive Helix, the Helix parameters dialogue offers several parameters specifying how the sketch should be swept.


This option specifies the axis about which the sketch is to be swept.

  • Normal sketch axis: selects the normal of the sketch that runs through the sketch origin as axis. introduced in version 0.20
  • Vertical sketch axis: selects the vertical sketch axis. This is the default for new helices.
  • Horizontal sketch axis: selects the horizontal sketch axis.
  • Construction line: selects a construction line contained in the sketch used by the Helix. The drop down list will contain an entry for each construction line. The first construction line created in the sketch will be labelled Construction line 1.
  • Base (X/Y/Z) axis: selects the X, Y or Z axis of the Body's Origin;
  • Select reference...: allows selection in the 3D view of an edge on the Body, or a datum line.


This controls what parameters will be used to define the helix. The choices are:

  • Pitch-Height-Angle: definition via the height per turn and the overall height
  • Pitch-Turns-Angle: definition via the height per turn and the number of turns
  • Height-Turns-Angle: definition via the overall height and the number of turns
  • Height-Turns-Growth introduced in version 0.20: definition via the overall height, the number of turns and the growth of the helical radius. So a Height of zero leads to a path in form of a spiral. A Height and Growth of zero to leads to a path in form of a circle.


The distance between turns in the helix.


The height of the helix (center-center).


The number of turns in the helix. Define as Height/Pitch

Cone Angle

Angle of the cone that forms a hull around the helix. Allowable range: [-89°, +89°].

Left handed

If checked, the turning direction of helix is reversed from default clockwise to counterclockwise.


If checked, the axis direction of helix is reversed from default.

Update view

If checked, the helix will be shown in the view, and updated automatically on every change of the parameters.


  • An additive helix that does not intersect the body will be visible in the preview if Tools → Edit parameters... → BaseApp → Preferences → Mod → PartDesign → AdditiveHelixPreview is set to true. The default for this preference is false. introduced in version 0.20


  • DataPitch: The axial distance between two turns.
  • DataHeight: The total length of the helix (not accounting for the extent of the profile)
  • DataTurns: The number of turns (does not need to be a whole number)
  • DataLeft Handed: See Left Handed.
  • DataReversed: See Reversed.
  • DataAngle: The rate at which the radius of the helix increase along the axis. Allowable range: [-89°, +89°].
  • DataReference axis: The helix axis
  • DataMode: The helix input mode (pitch-height, pitch-turns, turns-height)
  • DataOutside: Not used (Used in SubtractiveHelix)
  • DataHas Been Edited: If false, the tool will propose an initial value for pitch based on the profile bounding box, so that self intersection is avoided.
  • DataRefine: true or false. If set to true, cleans the solid from residual edges left by features. See Part RefineShape for more details.
  • DataProfile: Either a sketch containing a closed contour, or a face.
  • DataMidplane: Not used.
  • DataUp to face: Not used.
  • DataAllow multiple face: Not used.



Example helix using a B-spline in the sketch
Example helix where the helix axis is normal to the sketch plane resulting in a "Pad with twist" effect.