topic Re: Help! Surface loft error in Fusion Design, Validate & Document Forum

Help! Surface loft error

anton.soderlund_schulz.6265 — Sat, 15 Jan 2022 00:04:26 GMT

Hello, Im a student stuck on a surface loft.

I got the error/warning:

"Error: Cannot create surface from selected geometry.
Adjust the selection set.
Error: Cannot create tool body for loft."

This is only my second surface loft ever, so im correcting mistakes as I go (aligning points and such). But I can't figure out what the problem or solution is with this error.

The error appears when i select the rail, which by the way seems to be closed and connected to the profiles.

The other half works fine, so please please help me understand! Time is of the essence, huge thank you.

Re: Help! Surface loft error

anton.soderlund_schulz.6265 — Fri, 14 Jan 2022 23:50:48 GMT

By the way I just tried using a centerline and the error did not budge. Please help 🙂

Re: Help! Surface loft error

jeff_strater — Fri, 14 Jan 2022 23:53:53 GMT

no one can help you without the design in question. Export it and attach it to your next reply. However, one comment I can make is: you have way too many fit points in your splines. No way of knowing whether that relates at all to the error you are seeing, though.

Re: Help! Surface loft error

anton.soderlund_schulz.6265 — Sat, 15 Jan 2022 00:08:58 GMT

Thanks alot for responding. Okay exported and attached, I hope it was the right format. About the points in the splines, I projected a silhouette of a component i creating a pocket for. Is there a quick way to simplify the spline?

Re: Help! Surface loft error

jeff_strater — Sat, 15 Jan 2022 01:19:25 GMT

I took a different approach - instead of lofting one set of curves to the other, with one rail (which doesn't work , not sure why), I lofted from one set of curves to a point, with 3 rails:

(design attached)

But, that does not work with your design:

It will take me some time to explain all I did here. The original design was messy. Each profile had unnecessary lines in it, and as I said, too many control points. It took some time to clean those up. Look at my design in the meantime. The resulting surface is not great - you'll want to clean that up as well. But, the loft does succeed.

Re: Help! Surface loft error

jeff_strater — Sat, 15 Jan 2022 01:29:25 GMT

Here is a screencast showing what I did to one of the profile sketches to try to simplify it. Repeat that on all the sketches involved. You will have to be the judge of what is OK geometry, but in general, the fewer control points, the better.

Betreff: Help! Surface loft error

g-andresen — Sat, 15 Jan 2022 09:43:38 GMT

Hi,

here is a simple example of creating a "clean" spline.

günther

Re: Help! Surface loft error

TrippyLighting — Sat, 15 Jan 2022 10:43:18 GMT

I've gone through the timeline of your design and IMHO this is a complete redo from scratch starting with the first sketch in the timeline. It is not dimensioned and not properly constrained. It is also already overly complicated for the geometry you are creating. Fillets, for example, should not be part of that sketch.

Re: Help! Surface loft error

anton.soderlund_schulz.6265 — Tue, 08 Feb 2022 20:22:00 GMT

I solved it, thanks for the help.

Re: Help! Surface loft error

bryn.parrott — Tue, 27 Aug 2024 22:15:40 GMT

Always we find error messages of this nature, that give absolutely no clue as to what the actual problem is. Its now 2 years after this report, and yet I get it now too, so clearly Autodesk do not give it any priority to fix, but always we get new features nobody ever actually wants.

The useless error messages are by far the biggest impediment to productivity using Fusion.

Re: Help! Surface loft error

TrippyLighting — Tue, 27 Aug 2024 23:10:26 GMT

@bryn.parrott wrote:

Always we find error messages of this nature, that give absolutely no clue as to what the actual problem is. Its now 2 years after this report, and yet I get it now too, so clearly Autodesk do not give it any priority to fix, but always we get new features nobody ever actually wants.

The useless error messages are by far the biggest impediment to productivity using Fusion.

If you have specific problems, please open a new thread, post a model, and a detailed description of what you are trying to achieve and the problems you are encountering.

Re: Help! Surface loft error

bryn.parrott — Wed, 28 Aug 2024 00:04:42 GMT

No, I will not be doing that.

The issue of incomprehensible error messages (in general) is well known, yet never addressed by Autodesk.

What needs to happen, at the very least, is in the case where it is unable to complete the requested function to highlight graphically the areas of the model giving it difficulty : graphically making it clearer to the user what is the next step to allow the action to complete successfully.
To improve further then the error message needs to be written using language that makes sense to the user. At present the language used makes sense only to the programmer that wrote the code.

Re: Help! Surface loft error

davebYYPCU — Wed, 28 Aug 2024 01:55:22 GMT

What needs to happen, at the very least, is in the case where it is unable to complete the requested function to highlight graphically the areas of the model giving it difficulty : graphically making it clearer to the user what is the next step to allow the action to complete successfully.

So the upgrades performed for Loft Rail errors, (red blobs) - and yellow self intersection displays, are before your time?

There is / has been a continuing improvement commitment from Autodesk, in my time, admittedly more to do than they can handle.

Re: Help! Surface loft error

robinpowell46 — Tue, 14 Oct 2025 14:38:48 GMT

If you don't mind, how did you solve it?

Re: Help! Surface loft error

TrippyLighting — Tue, 14 Oct 2025 17:57:47 GMT

This is an old thread that is marked as solved. If you have a specific problem, it is better to open a new thread and post the problem there, preferably including the model in question 😉

Re: Help! Surface loft error

bryn.parrott — Tue, 14 Oct 2025 21:17:08 GMT

I do not see those. I am using current version. I agree that if they had such functionality it would be useful.

Re: Help! Surface loft error

TrippyLighting — Tue, 14 Oct 2025 22:41:50 GMT

@bryn.parrott wrote:

I do not see those. I am using current version. I agree that if they had such functionality it would be useful.

That functionality has existed for quite a while!

If you can share a particular case, please do so.

Re: Help! Surface loft error

bryn.parrott — Fri, 17 Oct 2025 00:16:11 GMT

Well, whilst working yesterday I noticed that when performing a loft, an error message does appears (!!) , and black lines indicate problem areas. I lok at the items highlights and do not see what its complaining about.
Language language of the error message is obscure and technical, not comprehensible to mere humans, and I do wonder why Fusion cannot just resolve the issues automatically, or at least be more helpful.

Re: Help! Surface loft error

TrippyLighting — Fri, 17 Oct 2025 11:56:20 GMT

What I meant with "If you can share a particular case, please do so." is that you would attach a model that exhibits the undesirable behavior in .f3d format. You could even post a screen recording.

For a software developer, your textual description is as obscure as the error message 😉

Re: Help! Surface loft error

TheCADWhisperer — Fri, 17 Oct 2025 18:43:50 GMT

@bryn.parrott wrote:
I do wonder why Fusion cannot just resolve the issues

@bryn.parrott

Can you File>Export your *.f3d file that exhibits issue to your local drive and then Attach it here to a Reply?