I am trying to model a wing tip correctly for my Fokker Wulf for texturing but I am unhappy with what I have done - it doesn't align very well.

The first picture attched shows the curves I have used and the resulting lofts... they look O.K. until rendered.

Can anyone tell me how best to achieve the result that I am after I have tried LOADS of different ways but seem to be banging my head against the wall.