How to Edit Splines in Fusion 360
You would like to edit a Fit Point Spline created in Fusion 360.
Editing Sketch Geometry
Edit the sketch that contains the spline geometry. Right-click on the Spline in the canvas (model) > Edit Sketch.
Controlling splines is all about making sure you have the ideal amount of spline points. In general, you should have a spline point any time the shape changes direction. Always minimize the number of spline points.
Add (Insert) Spline Points
Right-click on the spline (it should be highlighted in blue) > select 'Insert Spline Fit Point' > a crosshair will appear when you hover over the spline, simply click anywhere on the spline. You can add as many points as necessary, but the goal should always be to keep the spline points to a minimum so you can control them.
Delete Spline Points
Simply select a spline point > delete key on your keyboard. Alternatively, right-click on a spline point and select delete.
Move the Whole Spline
Hover over the spline until you see the blue highlight. Click (hold) and drag the spline around. Note that it will only move in ways that it is not constrained. Sketch constraints applied to it will limit how you can move it.
Adjust Spline Points
Hover over the spline near the spline point. A white point will appear when your mouse cursor is over the spline point. Click (hold) and drag on the spline point. Release the point at the desired position. Alternatively, apply sketch constraints or dimensions to spline points to position them precisely.
Tip: Fit Point Splines
Remember, sketch constraints may restrict sketch geometry from being altered. To see sketch constraints, simply select the geometry and look for the glyphs/icons that appear - often near the endpoints.