we have these field definition volumes that were added in order to force G4 to take a step at the boundary of the constant field. 

The problem that is arising is that these volumes are overlapping with the tracker itself. How do we deal with this? Clearly this is kind of a hack from the start but perhaps there is a smart way of keeping this. Perhaps we don’t care if we are going to a 3D field map where the step size is not determined by this. 

For now, I’ll remove it from any new detector.

/Pelle