I'm new to Tinkercad, so please forgive me if my question is painfully obvious to everyone but me ...
How do you create a new primitive? That is, how do you create a shape so primary that it uses none of the pre-made primitives?
I ask because I'm in need of a cylinder with an elliptical cross section. I've looked through a bunch of primitives and was unable to find this shape. Alternatively, does stretching a circle along one axis give you an ellipse? If so, how can I stretch a cylinder with a circular cross section?