You are going to need to be more explicit.
What kind of rail ? stair rail ? guard rail ? railroad track rail ?
Borrowing from another member of this forum.
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Are you trying to draw a parapet wall that is curved in plan and
is not made from a chain of straight segments ?
If so, you can use the wall tool with the curved geometry method.
I am sorry, I obviously don't understand what you want to do.
Peter what is unclear? I have a balcony ,alright? I need a paraphet with columns !!! not a wall 110Cm....paraphet made of wood...metal whatsoever...I need to draw the paraphet along the balcony contour continously...