How to fillet ribs

[Anotherbloodyproject]

Hey, I seem to be having some issues filleting my ribs The internal fillets seem to work fine, smaller subsections of the external ribs have worked previously in testing and I can fillet the top edge but I'm unable to fillet the bottom edge of the external portion of the ribs in this model, I just get the error: Recompute failed! Please check report view.

unableToFillet.png (99.74 KiB) Viewed 386 times

Any suggestions? I'd like to just fillet it as it is, as that's less work But if that's not a possibility, as painful as it may be, would I have any more success sketching the plan view of the shape and extruding it as a single pad rather than doing the mutitransform?

ribFilletFailModel.FCStd

(877.03 KiB) Downloaded 8 times

Code: Select all

OS: Ubuntu 18.04.5 LTS (ubuntu:GNOME/ubuntu)
Word size of FreeCAD: 64-bit
Version: 0.20.29177 (Git) AppImage
Build type: Release
Branch: (HEAD detached at 0.20)
Hash: 68e337670e227889217652ddac593c93b5e8dc94
Python 3.9.13, Qt 5.12.9, Coin 4.0.0, Vtk 9.1.0, OCC 7.5.3
Locale: English/United Kingdom (en_GB)

[chrisb]

There is not enough space left for a 1mm fillet. 0.99mm works.

[Anotherbloodyproject]

Perfect! Thank you. LinearPattern003 length was off by 0.1mm!

Was that an eagle eyed spot or was there something I could've checked there?

[chrisb]

Was that an eagle eyed spot or was there something I could've checked there?

Some experience. When fillet fails, it is always a good start to try with a very small radius and increase it until it fails.

[NHSA_Rainer]

Hi,

Strange. I clicked on any line of the outer ribs and then chose fillet and it made it without any problem with 1mm size.

Rib_Fillet.JPG (142.55 KiB) Viewed 305 times

[chrisb]

When a fillet consumes exactly the adjacent face, but not more, then it sometimes works, but I would not rely on it. You are then in the range where the numeric precision of the calculations comes into play.