Sheetmetal workbench - unable to unfold round bracket

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SIXe
Posts: 153
Joined: Sat Mar 16, 2019 3:10 pm

Sheetmetal workbench - unable to unfold round bracket

Post by SIXe »

Hi,

I'm trying to use the sheetmetal workbench for the first time and cannot get a simple bracket to unfold. Probably I'm doing something wrong here as I have no experience with this workbench.

Here's the bracket:
bracket.png
bracket.png (44.29 KiB) Viewed 1876 times
And here's how it looks after unfolding:
unfold.png
unfold.png (26.39 KiB) Viewed 1876 times
I highlighted the flat face and hit “unfold”. The radius is not unfolded and as a result the part is not usable. How do I create this bracket so it unfolds as expected? Any hints appreciated.

OS: Debian GNU/Linux 11 (bullseye) (X-Cinnamon/lightdm-xsession)
Word size of FreeCAD: 64-bit
Version: 0.20.25645 (Git) AppImage
Build type: Release
Branch: master
Hash: 37d9757399b4c2ec30318eb88d7cd7c508246345
Python version: 3.9.7
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.2
Locale: English/United Kingdom (en_GB)
Attachments
bracket.FCStd
(58.65 KiB) Downloaded 31 times
drmacro
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Re: Sheetmetal workbench - unable to unfold round bracket

Post by drmacro »

Interesting, the distance between the tab in the flatened sketch is correct, but, it doesn't add the lines.

BTW, why do you have the Part (yellow icon) container? It is not needed, just an extra step. ;)
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
SIXe
Posts: 153
Joined: Sat Mar 16, 2019 3:10 pm

Re: Sheetmetal workbench - unable to unfold round bracket

Post by SIXe »

drmacro wrote: Sun Sep 26, 2021 5:18 pm BTW, why do you have the Part (yellow icon) container?
The bracket is supposed to comprise several individual parts. But I already failed at creating the first bit.
drmacro wrote: Sun Sep 26, 2021 5:18 pm It is not needed
You're right. For this example the part is superfluous.
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papyblaise
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Re: Sheetmetal workbench - unable to unfold round bracket

Post by papyblaise »

I flip the subject all over the place, with or without PartDesign, I can't roll it up if it's greater than 179 °
Attachments
demi braket.PNG
demi braket.PNG (11.31 KiB) Viewed 1752 times
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papyblaise
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Re: Sheetmetal workbench - unable to unfold round bracket

Post by papyblaise »

after a lot of disappointment
Attachments
bracket.FCStd
(115.84 KiB) Downloaded 32 times
bracket.PNG
bracket.PNG (21.71 KiB) Viewed 1622 times
SIXe
Posts: 153
Joined: Sat Mar 16, 2019 3:10 pm

Re: Sheetmetal workbench - unable to unfold round bracket

Post by SIXe »

After tweaking the angles, the part looks correct. Thank you for looking into that. I saw that you completely reconstructed the part in the sheetmetal workbench.

What was wrong with my version? Did I make a mistake or is it a bug? I was under the impression that you can build objects outside the sheetmetal workbench (e.g. using sketcher like I've done). Is that not the case?
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papyblaise
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Re: Sheetmetal workbench - unable to unfold round bracket

Post by papyblaise »

I do not know the composition of the coding, it seems to me that unfolding beyond 180 ° he does not know which side to go
you didn't make a mistake, and I wouldn't talk about a bug either
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Willem
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Re: Sheetmetal workbench - unable to unfold round bracket

Post by Willem »

Your approach is in principle good but not complete
- Make the fillet in the sketch (see image)
- Fill in the properties in the Basebend, Radius=50 and the desired thickness
Schermafdruk van 2021-09-28 10-07-13.png
Schermafdruk van 2021-09-28 10-07-13.png (21.19 KiB) Viewed 1536 times
Edit: The fillet in the sketch fails with R=5 and smaller and succeed with R=6 and bigger
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Willem
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Re: Sheetmetal workbench - unable to unfold round bracket

Post by Willem »

Here a video for making such a bracket
phpBB [video]
SIXe
Posts: 153
Joined: Sat Mar 16, 2019 3:10 pm

Re: Sheetmetal workbench - unable to unfold round bracket

Post by SIXe »

Thanks for the input and the screencast Willem. Much appreciated.
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