How to create an opening in a curved element?

The steps below describe how you create an opening in a curved element. In the example below we use two round tubes:


Use the function ‘intersection’ or ‘connect members/nodes’ to generate the intersection between both tubes:


Now the function ‘cut-out’ is visible. Use the function and select both tubes (confirm with escape). Now the parts that can be cut-out are indicated. Select the parts that you want to cut-out (and confirm with escape):


The result looks like:


Note: you can follow the same steps to create other shapes of openings. For example, you can create an oval opening with shell elements,...