topic Re: Problem lofting a wing in Fusion Design, Validate & Document Forum

Problem lofting a wing

Anonymous — Wed, 21 Feb 2018 13:45:06 GMT

Hi guys!
I'm a Fusion beginner, trying to model an airplane wing for 3d printing.

I have two airfoil profiles that I'm trying to loft with 2 rails, leading edge and trailing edge. Everything goes well until I select the second rail. That's when I get: Warning: The loft would intersect itself.
Try changing the inputs to avoid this. If you wish to build a self-intersecting shape, try building the shape using multiple lofts.

I just can't figure this out. Can you please take a look at the file.

Re: Problem lofting a wing

davebYYPCU — Wed, 21 Feb 2018 21:12:48 GMT

Couple of things experience has taught me...

One sketch per selection in Loft, works better than your sketch 19.

I think this causes the self intersection, but not sure

The Trailing edge itself was not tangent, and rails need tangential intersections.

Fusion slowed down with those airfoils with so many points in them, but got there

The Trailing edge position in rib 1, was not a consistent position with rib 2.

I made two more sketches and it works, might need some more profiles near the tip to remove the shrink wrapping ridge,

File attached.

Re: Problem lofting a wing

chrisplyler — Thu, 22 Feb 2018 01:09:21 GMT

Re: Problem lofting a wing

Anonymous — Thu, 22 Feb 2018 11:05:50 GMT

@chrisplyler and @davebYYPCU thank you so much for pointing out that...point. Of all the combinations that I tried yesterday, I never tried that one.

I have a another question. Next I need to make the wing hollow, with 0.4mm thick walls. I already tried Shell, didn't work. Then I duplicated the body, scaled it down and cut it out with Combine. It worked, but it's hard to achieve uniform 0.4mm wall thickness this way. How would you do it?

Re: Problem lofting a wing

davebYYPCU — Thu, 22 Feb 2018 12:10:16 GMT

Well i figure that's not the whole story, 0.4mm skin no spars no braces, then Leave it solid, and let the slicer do its job.

After skinning at 0.4 mm then wanting sparse internal structures, wish I knew, has something to do with reverse normals.