Hi Guys,

I'm trying to loft an elliptical wing with SW (2003 sp0).

I input the airfoils as curves and draw the leading and trailing edges as 3d sketches because the dihedral is elliptical as well (the mold will be cnc).

Right now I draw a root curve (about 100 mm) and a tip curve (1 mm) for the loft endplates and use the leading and trailing edge curves as guide curves.

The result is surprisingly acceptable except that the thickness goes down linearly (and not elliptically) so the airfoil gets progressivly thinner towards the root.

I don't want to draw another guide curve for the top becuase it would be massively complex (swetp elliptical planform AND dihedral).

I would have resized the airfoil curves and drawn them at regular intervals but this seems like a lot of work and I can't seem to be able to resize the skeches properly (read: not at all!).

Anybody have any thoughts on how I can do this?
Erez

Well, I think I have it...

I added another profile at about 80% span. It's not perfect but it's darn near.

Next step toolpaths, milling, moulding! (wish me luck)

If you split the top view of the wing planform into two parts at the tip of the wing, you can sweep the form using two rails. The trick is to first project the spline to a plane with the proper amount of eliptical dihedral so the two rail curve in 3 dimensions. With this method you only need a root airfoil.

This project would be a whole lot simpler in Rhino.

Bill

Thanks Bill,

I tried it but could not get it to work to my satisfaction...

How would it be simpler in Rhino? (don't know Rhino at all)

Erez