"I remade this. See if it looks better. There are a few tricks I used:
On the very edge of the flow surface there can be mathematical noise. I used a different segment of the surface so that the flow object was away from the…"
"The MakeUniform command will make the knot structure of the curve uniform, but leave the control point locations the same. This may change the shape of the curve drastically.
The Rebuild command will create a uniform knot structure and will…"
"On of the rail curves does not have a uniform knot structure. When you rebuild, both curves get a uniform knot structure. You can see this in the What command of one rails before the rebuild.
Open NURBS curve start =…"