Topological naming problem...will force me to stop using FreeCAD?!

[gigax]

Hello All,

I would like to share my experience regarding FreeCAD and its use in a commercial environment.

I've started using FreeCAD one year ago, in a startup company, with the purpose of designing sheet metal enclosures. I am an electronic engineer and I have little experience with commercial CAD packages, as I have only worked with Inventor several years ago, for a short period.

Anyway, this is my workflow:

1) Using the Sheet Metal workbench, I design sheet metal part.
2) Using the Part workbench I place cylinders and cubes and I subtract them from the original part in order to create holes and air ducts.
3) Using the TechDraw workbench I create technical drawings with dimensions etc...

I have designed approximately 100 parts, of various level of complexity, from very simple brackets with a few holes, to large panels with several bends and more than 100 holes. It's been a very nice journey, I have learned a lot and, very important, I have been able to bring my stuff in production.

I have also used the FEM, Raytracing, Spreadsheet and Image workbenches, but they have a minor role in my workflow.
...

Here is my problem: due to the topological naming issue, it's almost impossible for me to apply revisions to my projects, without incurring in massive corruption of the TechDraw documents. For example, if I just need to move, add or remove a hole, typically most of the dimensions in my TechDraw tables are corrupted, so I need to restart from zero with all the technical drawings...and sometimes it means several documents with tenths (or hundreds) of dimensions to be deleted and recreated.

I have tried my best to understand this problem and find solutions, but I ran out of ideas and I start thinking that I will be forced to give up with FreeCAD and move to a commercial software.

Am I the only one in this situation? It's really a pity for me, as I've spent one year learning FreeCAD, I love it... but now that I need to revise my designs I discover this issue!

Thank you All,


OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.23258 (Git)
Build type: Release
Branch: master
Hash: 78c6cc1362c39e3f1f778c52ae2a1c82badeec20
Python version: 3.8.6
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
Locale: Italian/Italy (it_IT)

[dcapeletti]

Hello, here is a link that shows you how to design to avoid such problems. Also you should consider trying the FreeCAD version of realthunder that solves the problem. In the future realthunder changes are expected to be pushed to the master branch. Regards

https://wiki.freecadweb.org/Topological_naming_problem
https://github.com/realthunder/asm3-wik ... -Naming.md

[drmacro]

unfortunately those techniques dont work for things like Path, Sheetmetal, and TechDraw since they inherently use generated geometry. those techniques should still be used to avoid the model breaking though.

the option at this point is is to use the realthunder branch.

[papyblaise]

Don't throw in the sponge right away, Romeo didn't make his pizzas on the first try
the best way I can find to plug or move a hole is to redo a Pad over it and redo another (or more)
you can also avoid this by not referencing the holes in relation to the faces, but on the general planes XYZ
I haven't checked, but I believe making a copy as a Shapebinder freezes the shape and allows it to be modified without risking renaming

[thomas-neemann]

my customers are just starting to use freecad. so that these problems do not occur there, I advise:

if you basically work with triangular areas from draft, you can decide when creating whether you "glue" them to the geometry or fix them to three points that are firmly anchored in the room.

for the 2d drawings i recommend qcad.

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[openBrain]

I agree with drmacro that unfortunately any strategy will fail with SheetMetal or TechDraw. ATM my best advice would be to give a try to ASM3 fork by @realthunder that addresses the topological naming issue, and hopefully may be merged in FreeCAD master in a coming time.

[papyblaise]

I tested my idea but it works
so I made a carbon copy of Body (yello) , to get Body001 (red) that I modify in my own way
I have the 2 versions
then I have to redo Page001

[GeneFC]

unfortunately those techniques dont work for things like Path, Sheetmetal, and TechDraw since they inherently use generated geometry. those techniques should still be used to avoid the model breaking though.

I cannot comment on Sheetmetal or TechDraw, but I have no problem making changes in the model and then using those changes in an existing Path Job. Sometimes a recompute is needed, but never a redraw or re-creation of the entire Path Job.

Gene

[gigax]

Thank you All for your feedback!

I will follow your suggestions, and hopefully I will find an acceptable solution.

Just a question regarding the Realthunder version: do you think it will work only with new designs, done entirely with this version of FreeCAD, or also with existing designs, done with FC 0.19?

thanks

[chrisb]

If he hasn't included Abdullah's latest improvements in Sketcher, you will destroy all sketches created with a version after 0.19.23300.