How to loft a 3D edge?

[Anonymous]

I’m still new to Fusion 360, coming from Vectorworks.

Seeking a way to create a Loft using a selected edge of a T-spline as profile. Is it possible? The attached screenshot shows an example starting T-spline with the chosen edge selected (highlighted in light blue). I've also created an (example) arc for the "path" if required.

But then what?

[jeff_strater]

You can loft through 3D edges.  There are a few tricks to it.

First, you can only loft from edges if you are creating a surface (Patch) loft.  

Second, with a model like this, you have to turn off "chain edges", otherwise, it will try to select the entire boundary.

And the other trick is regarding your "path".  I'm not completely certain what shape you are trying to get here, so I had to guess.  I think you mean the path should be used as a guide curve, correct?  There are two kinds of guide curves:  a "regular" guide (we call it a rail curve), and a "centerline" rail.  In the screencast below, I use a regular rail.  These kinds of rails must intersect the profiles (in this case the 3D edges), so you need to use Project Intersect to make certain of that.

I took a wild guess at what you were trying to do here:

hope this helps,

Jeff

[Anonymous]

Thank you for the reply and screencast. I've studied it, and I've duplicated it. I understand that a sketch must first be created on a plane — instead of lofting directly from a 3D spline as in Vectorworks.

Apparently the Loft I need should be broken down to first orthogonally "projecting" the 3D edge onto a rotated plane. But is it possible?

In Vectorworks, there's Convert to Lines command. It's like intersecting a 3D edge through a solid body to leave a 2D shape. Any equivalent? Or substitute? Or other solution?

[jeff_strater]

Hi @Anonymous,

I'll try to answer your questions, please feel free to ask follow-up questions if I don't get it right.

Yes, a Fusion sketch starts on a plane.  It is not required to only contain planar geometry, but commonly will.  Loft can use 2D or 3D sketch curves (for a surface loft)

If you want to use 2D geometry, the sketch Project or Intersect commands will do that.  Project takes the selected item and just does a projection along the sketch direction to create a 2D curve.  The Intersect command will intersect a selected body with the sketch plane to get a 2D curve, or if a curve is selected, will produce a sketch point.

If you would like to record your workflow, or provide some info about the desired results, I'm sure we can provide better answers.

Jeff