How do I get the screw modifier to go around the Y axis for a 2d Trace I want to recreate a chess piece (Bishop) by wrapping a side trace around the y axis. However, when I use the screw modifier, it decides the y axis isn't good enough and does this to me.



This isn't just an issue with my complicated line either, it seems that all bezier curves have this problem: here's a example of the what I'm talking about.



This shape, rather than pivoting along the y axis, pivots along a slightly tilted axis of its own. How do I fix this? Changing the center of origin doesn't help.

TL;DR 

Is there any simple way to tell blender to screw a trace around an axis ignoring an object's origin?

Thanks!
The screw modifier by default uses the Z axis, you can change this in the modifier options.

If the revolution axis doesn't correspond to the world Y axis its because your object is rotated in Object Mode.

Check your objects rotation in the 3D View > Properties Shelf > Rotation (N Key)