Join multiple curves at the same time

I have two parallel lines that I am trying to join the curves on both lines at the same time. But I also want them to stay two open curves and not become a closed curve.

The lines have many different curves and they are very close together so it is very hard to just select one side at a time to join.

When I join them, the ends move to meet each other and form a closed curve.

Is there a way to only join points that are touching?

Hello - please post an example file. It may be that SelChain is what you are looking for.


Preselect and then join?

I gathered that was the hard part - figuring out what to select… but just guessing.


This is what is happening. I want to have two different curves but it is joining to a point at the edge and making it a closed curve.

I am following a tutorial for this and when they join, it creates two different curves.

Try checking your moddelingtolerances vs object size. If your gap is less than the tolerance then Rhino joins without warning. This often happens when shapes are drawn freehand or scaled, or if the wrong template was used before importing another file.