Cannot Join Curves?

[11clock]

I am trying to attach these two shapes together by joining their curves, but it's not letting me despite having selected 2 nodes.

 

Edited May 11, 2022 by 11clock

[Alfred]

Welcome to the Serif Affinity Forums, @11clock.

You can only join open curves, not closed ones. If you click on the ‘Break Curve’ button (shown at the top of your screenshot) to break the curves at the selected nodes, you should find that the ‘Join Curves’ button becomes enabled.

[R C-R]

1 hour ago, Alfred said:

You can only join open curves, not closed ones.

Should the OP be wondering why, it is because nodes can connect no more than two segments of a vector curve, so closed curves already have two segments connected at every node.

However, often users do not want or need to join several curves, just to manipulate them as if they were both part of the same object, so for that you could group them or use Layer > Geometry > Merge curves.