Sketch modification with bended faces

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Thomn78
Posts: 18
Joined: Tue Apr 19, 2016 8:49 am

Sketch modification with bended faces

Post by Thomn78 »

Hi there,

I wanted to make some modifications on my file, by reducing the area of my square. But the fact is that i made bended faces inside this square. So when i reduce my area, the reduction operate and update up to the first bend operation I realised in my tree.
Like you can see in the pictures :
entire Blade .png
entire Blade .png (66.16 KiB) Viewed 1601 times
There you've got my piece (I'll give my file at the end)
Square reduction.png
Square reduction.png (54.79 KiB) Viewed 1601 times
here (without dimensioning it, i just reduces my square area in the sketch
No operated.png
No operated.png (44.84 KiB) Viewed 1601 times
But when in the historical, comes the first bending operation, then, my reduction is not considered anymore ... Such critical, because if I want to reduce just the area of my square I need to remake my Part from nearly the beginning...

Is there any solution to my problem ?
Thanks

Thomas
Blade.fcstd
(598.61 KiB) Downloaded 49 times
OS: Ubuntu 14.04.4 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.6698 (Git)
Build type: None
Branch: master
Hash: ca7c5d31a4d61f32a25b71025b14641a6e378328
Python version: 2.7.6
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17
jmaustpc
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Posts: 11207
Joined: Tue Jul 26, 2011 6:28 am
Location: Australia

Re: Sketch modification with bended faces

Post by jmaustpc »

This is almost certainly either because you have forked your model or its another example of the topological naming limitation.

If you don't understand what I mean, use the Google search box at the top of these forums and you will find numerous posts explaining what I am talking about.
Thomn78
Posts: 18
Joined: Tue Apr 19, 2016 8:49 am

Re: Sketch modification with bended faces

Post by Thomn78 »

I've only 1 active view on my screen. No forked model.
My problem is the updating of the tree, when I just reduce the area of the square. The square don't reduce when the first bend appears. In a logic way, when I make a modification, the operation after have to update with my modification, but in my case, it updates up to the first bending operation, but I want the bend to update with the new dimension of the square ... But it don't ...
jmaustpc
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Posts: 11207
Joined: Tue Jul 26, 2011 6:28 am
Location: Australia

Re: Sketch modification with bended faces

Post by jmaustpc »

I am on my mobile so I can't test your file until tomorrow my time, .... Have you run the dependency graph tool?

http://www.freecadweb.org/wiki/index.ph ... dencyGraph
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NormandC
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Posts: 18587
Joined: Sat Feb 06, 2010 9:52 pm
Location: Québec, Canada

Re: Sketch modification with bended faces

Post by NormandC »

I have checked the file and the dependency graph is linear.

As Jim surmised, you are encountering the topological naming problem. (It's been discussed numerous times on the forum, please do a search on those terms and you'll find out what it is).

When making a change in the first sketch, I get this error in the Report view:

Code: Select all

Traceback (most recent call last):
  File "/usr/lib/freecad/Mod/SheetMetal/SheetMetalCmd.py", line 149, in execute
    selFaceNames = fp.baseObject[1], MainObject = fp.baseObject[0])
  File "/usr/lib/freecad/Mod/SheetMetal/SheetMetalCmd.py", line 100, in smBend
    resultSolid = resultSolid.cut(reliefSolid)
<class 'Part.OCCError'>: BRep_API: command not done
Basically the fact your feature doesn't update is because your model failed to recompute. You will have to rebuild it.

And here comes another unpalatable truth: you have constructed your model badly. In any CAD software, you should only wait until the very end before applying fillets (or chamfers). Basing features on top of fillets is a very bad modeling practice as it weakens the model, and it's compounded by the topological naming issue, making this in FreeCAD a recipe for disaster.
Thomn78
Posts: 18
Joined: Tue Apr 19, 2016 8:49 am

Re: Sketch modification with bended faces

Post by Thomn78 »

Sorry for my bad modeling, it was my first part on FreeCad, and i started using FreeCad (from today), 2 weeks ago, so i must do bad things yet, but i'm trying to improve my skill with this soft :/

I'll check the forum as you told me Normand

At least, Thank you both for your help and advices !
Thomn78
Posts: 18
Joined: Tue Apr 19, 2016 8:49 am

Re: Sketch modification with bended faces

Post by Thomn78 »

I rebuilt my part, and still have the same problem :(
I wanted the really end to make my fillets, i can change the dimensioning, the first bend change with updating but not the second one, so the rest after the second Bend don't update with my modification ...

There you got my file :
Blade Rebuilt.fcstd
(363.61 KiB) Downloaded 37 times
I think I built it much better, let me know what do you think
Thank you

Thomas
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