the shape has twisted

Support Modeling
#1

so i made a curve in the shape of the CNN logo.
i put a tube on it - well tried to but might have been a few too many nodes or whatever they are called cos i chose to delete the back half of the tube.
then my old computer would play - slowly.
anyway why has it twisted around so at the right hand side it is ‘sideways on’ so to speak.
thanks all

Attachments

twisting shape.JPG786×495 36 KB

cnn.blend (496 KB)

#2

the bezier curve is making very sharp curves and the diameter of the tube cant go through without touching itself

#3

yes, but on the left of the picture one can just see that the “half tube” has rotated.
it should always be the open bit ONLY at the back.
thanks