The Split Curves button
allows you to split and trim curves, dividing them into new separate curves. There are three ways you can split curves.
Firstly, you can split selected curves when they intersect within a specified tolerance. This enables easier creation of surfaces from curves.
Secondly, you can split curves at a selected trim curve. This splits the initially selected curves, leaving the trim curve unchanged. You can then delete the curves to one side of the trim curve, which has the effect of trimming them back.
Finally, you can split a single curve at a selected point on the curve. This gives you the control to cut the curve in half, wherever you choose, rather than at a point where it crosses another curve.
Splitting Curves where they Cross
Splitting Curves at a Trim Curve