Problem using Loft

[andres_robinson]

Hi guys,

I'm trying to build this plane wing out from a DWG that I later converted to DXF. I have all the profiles aligned the way they should be, and already create a line to use as path.

I select the tool, select the profiles, choose the option to use a centerline, and press OK. All sketches hide but no solid is created.

Can please someone take a look and help me with these?

Thx in advance,

[davebYYPCU]

Quick check of the file, I could not loft either,

more checking, looks like you have all profiles in the same (3d) sketch, and I have not tried that,

I beleive that each rib has to be in it's own 2d sketch. 

There are also hundreds of spline/data points in each airfoil, not recommended either.

Might help.....

[TrippyLighting]

I doubt that this can be lofted successfully with Fusion 360. Your profiles are not comprised of splines but of an excessive number of line segments.

You can try to approximate the profiles very closely using a spline (one spline!) if absolute precision is not needed.

It's a little bit of work and requires some patience in adjusting the point location and tangent handles. 

[etfrench · Accepted solution]

One quick way to convert the sections to splines is to use the mesh tools.

1. Extrude each section a small amount (1mm works fine)
2. Export the extrusion as STL
3. Import the STL
4. Select the STL
5. In the Sketch toolbar select Mesh|Create Mesh Section
6. If the border of the mesh doesn't turn orange, you will need to move the cursor along the X axis
7. The previous operation will create a sketch with an outline of the section.
8. Edit the sketch
9. Select Mesh|Fit Curves to Mesh Section
10. Using the spline tool start at the rear of the section and select points along MeshSection until you reach the begin point
11. Repeat for each wing section

Here's a screenshot of the three sections lofted (without using a rail)

[davebYYPCU]

I will disagree here,

what makes steps 1 - 7 and 9, easier than step 8?

Original file had 3 profiles in the same sketch, and imported airfoil data.

[TrippyLighting]

No, you can put all profiles into one sketch, but I would honestly not recommend that either 😉

[etfrench]

The sketch referenced in Step 8 is the sketch created in Step 7   It takes longer to write down all of the steps than it does to actually do the steps.

[andres_robinson]

Worked like a charm!

Thank you very much!

[TrippyLighting]

@etfrench very cool method!

This workflow begs the question why we could not hav a best fit splien curve tool that would allow us to do this without having to resort to export/imprt .stl files.