Create lines from opposite points to represent beam

How do i create lines to join like the attached image so that i can use it as beams in karamba?

PTT (17.3 KB)

Why don’t you use your base rectangles?

PTT (17.3 KB)

thanks! And how did you list the items out (+1, +2, +3) as it usually just shows “i”?

Zoom in and you’ll find little + button.

You can also use this way