I am modelling a complicated tube frame and need some help!  I have been experimenting with 3D sketch and curves, but was wondering what the best way of doing it was??  Or a decent tutorial.  I have done the one on SW help, but it doesnt tell you how to sketch off axis, other than xyz planes.

The frame has complicted angles and needs to be very editable. The profile is the the same throughout. 

Many Thanks, Mike