Fatal error when filleting

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Joined: Thu Nov 30, 2017 9:47 am

Fatal error when filleting

Postby AndreKR » Sun Jan 06, 2019 8:32 pm

Please see the attached file.

I am trying to fillet this edge:
2019-01-06-21-27-50-FreeCAD.png (12.8 KiB) Viewed 297 times

But I just get a broken body with different errors (with the Part workbench Fillet tool). At first (when I had more edges selected) I got "BRep_API: command not done" but now I'm just getting "A fatal error occurred when making fillets" With the Part Design workbench Fillet tool I'm getting "Access violation".

Bug or user error?

I am using a development release though.

Code: Select all

OS: Windows 7
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.15536 (Git)
Build type: Release
Branch: master
Hash: 98ebeaa198df945ba666c15912c6caf95920f0ef
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: German/Germany (de_DE)
(56.28 KiB) Downloaded 16 times
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Joined: Tue Mar 17, 2015 9:14 am

Re: Fatal error when filleting

Postby chrisb » Sun Jan 06, 2019 9:02 pm

Fillets are sensitive beings. Among others they don't like too small angles at the joints. I would redesign the holder and let the outer arc go through from one end to the other.
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Re: Fatal error when filleting

Postby ppemawm » Sun Jan 06, 2019 9:15 pm

AndreKR wrote:
Sun Jan 06, 2019 8:32 pm
Bug or user error?
If you zoom on the juncture between the arc and face21 you will see a discontinuity which the fillet cannot handle. The reason is the dimension 5 mm thickness in your sketch003. As Chrisb noted, even if you fix the thickness the fillet may succeed but the solid will likely be invalid. It would be better if you can redesign it to make that transition tangent.
Picture1.png (85.38 KiB) Viewed 280 times
"It is a poor workman who blames his tools..." ;)
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Re: Fatal error when filleting

Postby user1234 » Sun Jan 06, 2019 9:18 pm


There are small edges in the 3D - model. The OCCT kernel will strike there.
Screenshot from 2019-01-06 21-40-09.png
Screenshot from 2019-01-06 21-40-09.png (33.15 KiB) Viewed 280 times
Screenshot from 2019-01-06 21-40-37.png
Screenshot from 2019-01-06 21-40-37.png (22.92 KiB) Viewed 280 times
You can do by te last Pad the option "Refine Shape = true", then you can fillet the outer eges, but no more. I think you should remodel your part so that there is no unnecessary edge is in it.
Screenshot from 2019-01-06 22-07-19.png
Screenshot from 2019-01-06 22-07-19.png (60.33 KiB) Viewed 280 times
Sorry for bad english.
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Re: Fatal error when filleting

Postby meme2704 » Sun Jan 06, 2019 9:37 pm

I have a little overhaul your sketch, and now it works, and even a little more (I put it too :?: )
porte-gobelet.PNG (29.15 KiB) Viewed 274 times
porte gobelet.FCStd
(237.29 KiB) Downloaded 10 times
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Re: Fatal error when filleting

Postby AndreKR » Sun Jan 06, 2019 9:38 pm

Thank you. I replaced the old length constraint with external geometry and a coincident constraint and now it fillets nicely.