Loft preview looks good but then gets mangled

[Anonymous]

Hello, I'm trying to create a little necklace charm with a twist in it. When I attempt this with a loft, the preview looks perfect, but gets mangled when I click OK. Please see attached screen capture GIF. Any thoughts on how to make this work? I've tried this on both PC and Mac with the same results. Thanks!

[jeff_strater]

yes, that looks like a bug.  Can you share the design here so we can take a look?

[Anonymous]

Is this what you need? https://a360.co/3GxM6Ou

Thanks for the quick reply!

[jhackney1972]

Please attach your model.  I do not get the same result from a sample file.  If you do not know how to attach your Fusion 360 model follow these easy steps. Open the model in Fusion 360, select the File menu, then Export and save as a F3D or F3Z file to your hard drive. Then use the Attachments section of a forum post to attach it.

[jhackney1972]

You either did not Share the Model or you are on a Fusion 360 Personal License.  Follow my instructions on how to attach your file, works everytime.

[Anonymous]

Oh I see. Attached is the model. Not sure if it matters, but this is exported with the mangled loft applied. Thanks!

[jhackney1972]

You can edit the Tangency Weight to suit.  

Edit: I edited the lower shape and raised the top a little to get a better transition in the second model.  You really need to constrain your sketches.

[Anonymous]

Oh cool. I'll try that. Do sketch constraints help the other tools do their thing? This was just a quick little design I whipped up just to get a price quote. Thanks again!

[jhackney1972]

Yes and they mainly help you maintain your desired shape.  Fusion 360 has to recalculate all sketch geometry that is not fully constrained every time the model updates.

[jeff_strater]

thanks for the model.  This is definitely a bug, I will report it. 

[edit] created bug FUS-95828 for this issue

[jeff_strater]

@jhackney1972 - how did you do this?  I reproduced the original problem with the original file.  Your version has a couple extra Extrudes of .01mm, I don't get how that fixes the problem...  You are some kind of wizard, I think.  😀

[TheCADWhisperer]

My attempt...

[Anonymous]

That's awesome! What did you do? 🙂

[TheCADWhisperer]

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@Anonymous wrote:

 What did you do? 🙂

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