Loft feature creating weird ridges.

alex_holtzman_

https://cad.onshape.com/documents/2ff341adf60a1fa46600d7af/w/e7e3892145738f61dfb2ccae/e/a3b3d0832470a1a18cfbd167

I'm trying to create a model by lofting multiple surfaces together as like slices of the 3d model but for some reason it doesn't smoothly loft so it creates these weird ridges. Anybody know a fix?

S1mon

There are a few problems:

1. Your sketched curves are not that smooth. The standard spline tool in sketcher is really only good when you have a lot of points that you have to go through, and you don't care about curve smoothness/fairness. Using Bézier curves would be much better. You would likely need to split up the model into more basic shapes like a fuselage, canopy, tail, wing, etc.
2. You have too many sections and they are too different in the number of points and shape.
3. You don't have guide curves and you didn't use connections to help Onshape understand what you might intend.
4. You used a loft for each section and you used loft instead of boundary or even fill.

I tried just fixing #3 with a single loft using connections, and I can get a loft which is slightly less bad, but the connections are hard to manage and it still doesn't produce a good surface.

It really depends on what your goal is. The surfacing tools in Onshape can produce high quality results, but a shape like this is going to be a very challenging project without a lot of experience.

If you're going after something that's just going to be 3D printed that's more of a toy-like shape, you might be better off with a polygonal/subdivision tool like Blender or Nomad Sculpt.