Sketcher BSplineInsertKnot

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Sketcher BSplineInsertKnot

Menu location
Sketch → Sketcher B-spline tools → Insert knot
Default shortcut
Introduced in version
See also
Sketcher BSplineIncreaseKnotMultiplicity, Sketcher BSplineDecreaseKnotMultiplicity


The Sketcher BSplineInsertKnot tool inserts a knot into a B-spline. If a knot already exists at the specified parameter its multiplicity is increased by one.


  1. Select a B-spline.
  2. There are several ways to invoke the tool:
    • Press the Insert knot button.
    • Select the Sketch → Sketcher B-spline tools → Insert knot option from the menu.
    • introduced in version 1.0: Right-click in the 3D view and select the Insert knot option from the context menu.
  3. Move the cursor to the desired location.
  4. The current position is marked with a small circle and its parameter value is indicated.
  5. Click to insert a knot, or click an existing knot to increase its multiplicity.
  6. This tool always runs in continue mode: optionally keep inserting knots and/or increasing multiplicity values.
  7. To finish, right-click or press Esc, or start geometry or constraint creation tool.