GD&T Workbench for FreeCAD

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vanuan
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Re: GD&T Workbench for FreeCAD

Post by vanuan »

Here's an example from the standard that compares 2D representation, 3D representation/model, and the meaning
Screenshot from 2020-09-24 20-23-46.png
Screenshot from 2020-09-24 20-23-46.png (184.78 KiB) Viewed 2814 times
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vanuan
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Re: GD&T Workbench for FreeCAD

Post by vanuan »

Created some illustration/desired UI
Tolerancing_Annotated_Design_Model.png
Tolerancing_Annotated_Design_Model.png (85.38 KiB) Viewed 2749 times
carlopav
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Re: GD&T Workbench for FreeCAD

Post by carlopav »

vanuan wrote: Sun Sep 27, 2020 8:34 pm Created some illustration/desired UI
Some ideas may be coincident with what is outlined in a post by realthunder that I crossposted in the Arch subforum: https://forum.freecadweb.org/viewtopic. ... 80#p426540
follow my experiments on BIM modelling for architecture design
cadcam
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Re: GD&T Workbench for FreeCAD

Post by cadcam »

@vanuan

This looks really nice.
I seem to have missed it, but is this an output from a new GD&T code
or a resurrection of the original?

Given the way GD&T is being used in industry output is needed in
2D (TechDraw?), 3D representations and also CNC/AM output models.
Will the code allow for the data to flow and be used by all these forms?
Or at least a API made available ?

The point of entering GD&T data can be varied depending on the
individual/company workflow. Is the data associative between Sketcher/2D/3D?
e.g. It would be really nice to be able to tag specific tolerances when sketching and
have them displayable and editable in later stages of the design. As has been
pointed out not all dimensions require specific tolerancing but being aware of those
that have been defined while re-editing a sketch would be nice (mark/different colour)
and access to direct display and/or pop-up menu would put FC up with other leading CAD.

[I am afraid I haven't read all the forum threads so may have missed a critical thread,
but this type of GD&T usage is only part of the move to Model Based Definition (MBD)
[PIM, BIM for buildings..]
and as such I wonder if a wider discussion is required about common data entry styles for
additional data and display formats for 2D and 3D representations of parts/assemblies.
Some early careful thought (may already have been done!) about how to tag/identify different types
of data, e.g. size/tolerance/supplier/material treatment/maintenance/disposal, and filter
display formats (Drawings, BOMs, BIM might save significant duplication of work in the future.]

My 2 pennies worth may be complete of target, but please continue with the good work on
GD&T

Best Wishes
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vanuan
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Re: GD&T Workbench for FreeCAD

Post by vanuan »

cadcam wrote: Mon Sep 28, 2020 8:35 am I seem to have missed it, but is this an output from a new GD&T code
or a resurrection of the original?
This is just a picture that illustrates the standard described in ASME Y14.41
cadcam wrote: Mon Sep 28, 2020 8:35 am Given the way GD&T is being used in industry output is needed in
2D (TechDraw?), 3D representations and also CNC/AM output models.
Yes, we need a FreeCAD object model that can support 2D, 3D and STEP files.
cadcam wrote: Mon Sep 28, 2020 8:35 am Will the code allow for the data to flow and be used by all these forms?
There's no such code available. But yeah, there should be.
cadcam wrote: Mon Sep 28, 2020 8:35 am The point of entering GD&T data can be varied depending on the
individual/company workflow. Is the data associative between Sketcher/2D/3D?
e.g. It would be really nice to be able to tag specific tolerances when sketching and
have them displayable and editable in later stages of the design.
I'm not sure if the future FreeCAD object model should be based on Sketcher or 3D primitives. I think it should be based on the Part objects (be a part of the PartDesign workbench) as GD&T is specifically about manufacturing parts that need to be assembled.
cadcam wrote: Mon Sep 28, 2020 8:35 am As has been
pointed out not all dimensions require specific tolerancing
Yes. According to standards and common sense, only part surfaces that touch other parts are a subject of GD&T.
cadcam wrote: Mon Sep 28, 2020 8:35 am but being aware of those
that have been defined while re-editing a sketch would be nice (mark/different colour)
and access to direct display and/or pop-up menu would put FC up with other leading CAD.
I'm afraid this would not be possible without heavy changes at the core of FreeCAD. As the toponaming issue is not solved I consider FreeCAD documents to not be editable.
cadcam wrote: Mon Sep 28, 2020 8:35 am and as such I wonder if a wider discussion is required about common data entry styles for
additional data and display formats for 2D and 3D representations of parts/assemblies.
FreeCAD supports so-called View objects. Those are considered to be a view-only representation of the data model behind them. An example would be a Section View object in BIM/Arch workbench.

Not sure if this is what you mean.
cadcam wrote: Mon Sep 28, 2020 8:35 am Some early careful thought (may already have been done!) about how to tag/identify different types
of data, e.g. size/tolerance/supplier/material treatment/maintenance/disposal, and filter
display formats (Drawings, BOMs, BIM might save significant duplication of work in the future.]
Yeah, FreeCAD object tree and property editor need some love and rethinking from UX perspective. BIM workbench has initial support for layers. Something like this is needed for part / assembly too.
akredd
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Re: GD&T Workbench for FreeCAD

Post by akredd »

vanuan wrote: Wed Sep 23, 2020 3:05 am
akredd wrote: Fri Apr 03, 2020 4:46 pm The problem is, I can have a look at ISO 1101 and 25178, but not on ISO 16792. And I know that it is not allowed by law in Germany to share ISO's. You have to buy them at Beuth-Verlag. :(
FWIW, the basis for ISO 16792 is ASME Y14.41. Which can be downloaded from here: http://gost-snip.su/download/asme_y14_4 ... _practices

But I think you also need the ASME Y14.5: http://www.sharifcadcam.ir/uploaded/2e2 ... 686c4f.pdf

Not sure what's the difference between ANSI standards and ISO standards. Maybe it has something to do with the imperial vs metric system difference.
Hallo,
sorry that i was absent a long time.
Thank you for the above links. I downloaded it and will try to understand them...
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RedBaron
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Re: GD&T Workbench for FreeCAD

Post by RedBaron »

Hello
Will the GDT Workbench be further developed?
I get this message in Addon Manager:
This addon is marked as only for Python 2

This workbench may no longer be maintained and installation on a Python 3 system
will most likely result in errors at startup or during use.
About Information:

Code: Select all

OS: Linux Mint 20 (X-Cinnamon/cinnamon)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.22670 (Git) AppImage
Build type: Release
Branch: master
Hash: 12155f4aab09047c5697db0c1b3cf93b02edda03
Python version: 3.8.6
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.4.0
Locale: German/Germany (de_DE)
Thanks for your help and kind regards
RedBaron
carlopav
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Re: GD&T Workbench for FreeCAD

Post by carlopav »

RedBaron wrote: Tue Oct 13, 2020 7:46 pm Hello
Will the GDT Workbench be further developed?
Hello! As far as i can Say it's not manteined at the moment. So Who knows what the future will bring :)
follow my experiments on BIM modelling for architecture design
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uwestoehr
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Re: GD&T Workbench for FreeCAD

Post by uwestoehr »

Sorry for cross-posting, I started to develop at least the basic GD&T features to TechDraw for the reasons I described in this post: https://forum.freecadweb.org/viewtopic. ... 20#p461320

So before developing a 3D model allowing to im-/export to Step and the like, it is desperately (sic!) necessary to be at least able to draw tolerance frames in TechDraw. In my opinion TechDraw's balloon feature just has to be adapted a bit to achieve this.
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RedBaron
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Re: GD&T Workbench for FreeCAD

Post by RedBaron »

@ uwestoehr
Thank you for the effort to extend the TechDraw Workbench.
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