how do I Draw a cylinder on a non axial line?
SU’s tool orientation is predominantly based upon camera orientation relative to the current drawing axes orientation.
Simply use the Axes tool or the Axes Context Menu to temporarily align the Drawing Axes to the line.
Then, create a Scene with Axes Location properties to return to that custom axes setting if needed.
Upon completion, click ‘Reset’ in the Axes Context Menu to return them to their default position which is aligned with the (inalterable) internal World Axes.
Another possibility is to draw the cylinder on an axis and then rotate it to match required line.