So, I have been modeling tubes and such in a number of projects and I keep running into the same problem. I have been modeling the tubes with curves and then using the bevel depth and bevel resolution options to create the tubes. The problem lies in when I add a number of divisions to the tubes I get twists in the tube. (rotations) Is there a way to easily get rid of these twists?
Your curve, the one along which you extrude your profile, must never point in the same direction as its own (local) Zaxis.
This may become difficult to avoid if you have a long run of tube that turns in just about every direction. Try to split them if they are too long.
One remedy that will work in many cases is to use a hook on all the control vertices and ‘rotate’ the object. It won’t rotate to the eye, because of the hook, but the twist will disappear.
Thanks a lot!