FreeCAD Is Fundamentally Broken! - Now what... Help Me Decide... 

I am a former employe of Dassault Systèmes and used Catia V5 since about 20 years (plus UG, Inventor, Blender, Fusion, etc). So glad to see such an amazing open source software as FreeCad. Amazing work done by the community. However, it makes me sick to hear here and there from users people talking about "Good practice" when in fact it is work around and silly tedious contortions for a massive issue other CAD softwares deal prefectly with since eons. If a parametric software CAN'T deal with topological naming correctly... well... it is NOT a parametric CAD. Glad to hear that a non official branch solved most of the issues, but knowing the problems with files compatibility from one version to the other in freecad, let's hope this set of fixes will be integrated in the official version soon and make finally Freecad dominates. I teach FreeCad and seriously, other than that issue, it is amazing!

If freecad wants to become the CAD standard, it has to fix a BUNCH of quality of life issues.

I'm also one of the developers. Thanks for tackling this in a respectful and educational way instead of just throwing shade. Your video is a really good explanation of the topological naming 'problem'. -- I disagree with you on that particular point. It isn't a 'silly bug' or something easily overcome. (If it was that easy, it would have been resolved long ago). It's called a 'problem' because the issue is intrinsic to parametric modeling. It can never be 'solved', only mitigated and avoided. In fact, if you know what you're doing, you can trigger a parametric model to break in _any_ parametric modeling software. Admittedly, most software handles/avoids it better than FreeCAD does currently but I don't think it's possible to ever say it's 'solved'. Realthunder's linkstage is a huge improvement and I can't wait to see his fixes become part of FreeCAD. I don't have good advice for you about how to make your videos. I would suggest that you should always stress good design principles which avoid breaking models. That means all the techniques you mentioned. Thanks for doing this and keeping the discussion professional.

Considering RealThunder's patches are going to be implemented in the main branch eventually, it stands to reason that FreeCAD will perform somewhat like RealThunder's current branch at some point in the future. I say go for it with the RealThunder branch videos for now. Irrespective of obsolescence, things move so quickly these days anyway, we might as well make the most of the FOSS software we have now, while we can!

I watched this video a few days after taking your freecad turorial. About 2 months in working with FreeCAD, I started experiencing this issue while editing bodies and I kept this information in mind. It really helped me not lose my mind knowing this has nothing to do with my skills but a limitation of the tool itself

I use FC once in a while to design very simple parts for 3D printing. I don't have much CAD experience, but made my living before retirement as a software engineer. Clearly this problem is a serious design flaw, whether or not "bug" is the right term for it. I have read quite a few forum threads etc. on this, and have often encountered comments to the effect that, well, you shouldn't use CAD software that way anyway. Also, there are plenty of remarks to the effect that this is a hard problem to solve. It may be a difficult problem to solve, but a lot of comments excusing FC miss an important point. Take the "simple" example in this video that demonstrates the problem (three stacked rectangular bits). If, to a human user, the identity of the faces,, or features, is clearly retained through the edit, and the intended result is conceptually clear to a human, then there is a software solution to the problem. If the software does not produce expected results which can be clearly defined by the human user, the software is WRONG. I acknowledge that (software implementation aside) there may be cases in which an alteration or transformation creates ambiguity about the identity of the resulting geometry, and what would constitute "correct" results. But that is clearly not so for many simple instances where the topological naming problem creates unexpected, and clearly wrong results. So really, there is no good reason to accept the current behaviour and work around it, at least not for long.

This *exact* bug has literally driven me to tears of frustration. Like, I was trying to design a fan duct for a 3d printer. My boss wanted me to change a "few little things". *Every single time* I changed anything, it would run into this exact issue. It got to the point where it just was less of a hassle for me to just delete the sketches I made until I get to the semi starting point, then re-make the sketches *with* those changes baked in. Honestly, this kind of thing is a major reason why I still have zero patience for FreeCAD any time any minor thing goes wrong.

A Video about the Datum Plan Workflow sounds really useful. I don’t think that video would become outdated, when the topological naming problem is solved. Sounds more like a useful concept that could be handy in tricky situations.

Please teach us how to use FreeCAD in it's current state, even with the workarounds. Why? Because even with the inconveniences, it still makes CAD design accessible to those of us who can't afford the Fusion tools at their ridiculously high prices. When and if FreeCAD fixes their bugs, you can still do new videos. It's better to have useful info on a cumbersome product, than to be able to use no product at all.

I do CAD works occasionally and I'm getting to know FreeCad lately. I like it! And yes, I also fall into that "bug" once. When it happened I didn't realise what sort of sorcery happened in front of my eyes and just removed shapes and stacked them up again. Not a big deal. Wish not to pile up things in some bigger project though...

Let's go for origin and datum tutorials. It's a skill that never gets obsolete and makes you a better modeler on ANY cad :)

I was on the design team for the B-1B armament and weapons loader trainer, designer of the ejection seat inert training modules. some how a real ejection seat munitions module got int the training room and on to an ejection seat. No one was in the seat and they were showing what handle to pull and it went off sending the ejection seat thru the roof of the hanger. There was about 10-15 different modules. I accomplished the project that was adopted air force wide. I started out as a apprentice manual machinist at a local textile factory and went to work at Kelly AFB and was a journeyman machinist until I got into drafting and became a draftsman. I then went to Randolph AFB as a engineering tech and worked on the B1-B project till it finished and retired at 56 yrs old. We were on computer vision software and did 3D wire frame design. I'm starting my small machine shop up and needed a cad program for an 82 going on 83 yr old man. I'm having a learning curve on FreeCAD as my mind is still thinking computer vision. But come hades or high water I'm gonna win..

This bug is exactly why I said "Fuck this! I'm already using Blender, can't I just CAD model in there?", and that's how I found your channel and Blender Precision series!

Same there for Siemens NX: As a power user, I can say that for robust models you should AVOID referencing on faces or edges. The robustness hierarchy is : 1. coordinate systems 2. planes 3. faces 4. edges

These tutorials are very good! I've been a Blender user for over a decade and just recently started exploring Freecad for a work project. I'm very much looking forward to following your tutes and learning this new program! Thanks!!

I want to use FreeCAD when I need to use a solid modelling type program vs. the surface modelling program I usually use. Thanks for letting me know about this issue. I did try to learn FreeCAD but haven't had much time to really get in to it. I ran across an issue with just trying to scale a part. It wouldn't let me do it. It wanted me to make a copy of the part I had created then would let me scale the copy. I wanted to scale the original as I realized I used the wrong units when I started the model. For now, I continue to do most of my work in Rhinoceros 3D.

Several years ago when looking at cad programs, I took one look at the fusion 360 license terms, foresaw pretty much what happened, and went elsewhere. Losing full access to my own design drawings because of a software and license update was not a risk I was willing to take.

RealThunders branch!! Focus on core features as they will apply to future releases. Waiting for the series :-)

I use different CAD software depending on the model I need to make and the purpose of it. I really like the FreeCAD spreadsheet function, and I was comfortable using datum plane referencing from the beginning, but it was tedious before they added the ability to set certain plane offsets with spreadsheet functions. At this point, I can usually create whatever I want unless it contains fillets. The name topology absolutely ruins these to the point where the fillet needs to be the last operation in your part, after which you can never edit anything again. Since Fusion360 added in more restrictions for the free version, I've moved away to Solid Edge, which is basically magic for editing step files. I'm still not super used to the workflow of editing so many things in 3D instead of sketches, but I find that CAD skills are transferable regardless of the software you choose.

I think FreeCad is fundamentally good. It was never broken but it does/did take an effort to learn to drive properly. The more I learn about it, the more power I find it has. I accept that other 3D modelling programmes are available. As a retired engineer I find Freecad's clean presentation a bonus.

Just tried in 0.20.2, still broken. In fact, when I tried, the top cube appeared to be randomly placed inside the bottom cube, not even touching the second cube, so work that out! In my first attempt I got a "result has two objects, not supported", which made no sense either.

On another point, the best way for a free cad program to spur adoption is to open itself to customization in UI so that it can be refamiliarized for people transitioning from other CAD softwares. I really can't stress how underestimatedly important that is. Shortcuts, button placement, mouse controls, etc is really what makes or breaks it for being able to fluidly jump from different programs.

THANK YOU for making this video! About the program I love and the bug that I hate. And suggesting RealThunder branch - I didn't know that option existed. It is absolutely CRAZY that RealThunders patches have not yet made it into the master branch of FreeCAD. I completely agree that this "topology naming problem" is not a "problem" but rather a "program crippling bug".

The beauty of FreeCad is there's more than one way to accomplish the same thing. Just make three separate sketches and merge them when you're done. No bugs, easy af.

I've been using freeCad for 3d modelling for 3d printing for quite a few years now and while I hit this bug initially due to the tutorials telling you to reference existing faces, I quickly changed my processes such that haven't had to deal with it at all because I never reference any of my sketches to a prior face in the body. If I absolutely need to base a sketch of a face then I create a sketch that is referenced to the face and then copy it's parameters into a new sketch that is not referenced to anything. One major benefit of that is that I can re-organise my entire model however I want moving sketches around freely. Edit: Honestly I just wish I could single click to re-align a sketch to any face's parameters and that would be the end of it. There is no need to lock it to a named face

Anyone watching this in 2023+ ... 0.20.2 was released on schedule and works well. We are currently using 0.21 (Beta) for a large Architectural model and it's been great. 😍 FreeCAD certainly has quirks and steep learning curve but it's worth the effort to learn and us it. Beats paying obscene amounts to RENT closed source software.

Thank you for this video. Great explanation of the bug and workarounds. I agree with you. FreeCAD's success/popularity would be better if this bug was to be corrected and the solution already exists.

Wow. Hard to understand how it ever even got out of beta with a bug like that.

I haven been using some 3D modeling software long before I got into 3D printing and encountered Freecad. And I thought "What the hell is wrong with this program? Why does editing the shapes you made your object of end in breaking it all at least 50 % of the time?". To edit things I then used to delete the last step(s) and do it all over. Then I discovered re-referencing. Still it's unbelivable that this hasn't been fixed years ago. This is not how things are suposed to work. Your comparison with a cliff actually totally expresses how it feels. Although technically your cliff function, that isn't a real function, would take you back in time xD .

I would love to hear all your opinions in the comments! Plus here is a Poll to let me know your thoughts if don't have the time or don't feel like leaving a comment: ru-vid.comUgzDDe5XmIku-jQEJ7N4AaABCQ

This is the first I've heard of RealThunder but the bug you mention drives me insane. In the race- quadcopter world, open source programs have grown into multiple variations from original projects. It's an evolving software that respects it's origins and it works.

Has the current stable version 0.20.2 of freeCAD fixed this issue or is it still advisable to use the Realthunder branch? Thanks

Thank you very much for making this video! I've been putting up with FreeCAD for a long time, just because it is free. I've often wished that the developers of Blender and KiCAD would take over the FreeCAD project.

I am a new user of FreeCAD and still trying to learn how to use it. In that light I want to say thanks for making this problem known and explaining it is such a plain and easy to understand manner. BRAVO! You ask for advice on how to proceed with your tutorials. It is now late in 2022 and the 0.2 version is available. And you have made another video letting us know this problem has not been fixed. Again, thanks! But you asked for advise and that is a loaded question. It really needs a crystal ball, but mine was broken some time ago. Let me digress a bit. I am a long time CAD user. I first started back in the 80s. I needed an inexpensive but capable and EASY to LEARN 2D program which could be used for TV station design - the technical system, not the building. I settled on EasyCAD which was around $60 back then (my employer was not going to pay for it) and available for a 30 day trial. The name and the price were the main features that lead me to it. And it lived up to it's name. I was doing drawings after only about two hours of familiarization. Why do I mention it? Because of it relative ease of learning how to make drawings with it. I had tried a friend's copy of AutoCAD and after about a week of "learning" I was no closer to my first drawing with it than when I first sat down to that trial. In my mind there is a very big advantage in a CAD program that is easy to learn. One that is intuitive. My advice to you is not about what version of FreeCAD to make your videos on, but rather about how those videos should be taught. I know that a program like FreeCAD or any of the other fully functional 3D CAD programs are not and can not be as easy to learn as EasyCAD was back in the 80s. But one thing that I find missing in almost all of the video tutorials is an explanation of the basics of how the program operates. An example of this would be Fusion360 which I have tried over the past two years. Every video I can find simply starts into a "learn by example" scenario. While this may get you off to a flying start, you don't know the details of your airplane. How many engines? What kind of engines? Type of landing gear? Even the wing arrangement? In Fusion that means that I still, to this day and after designing several projects with Fusion, I do not really have a good grasp of the hierarchy and relationships between the various features in a model. Or what goes into the file when I save a part. I never learned how to make a number of different parts that are in an assembly in the same model/file. And I am struggling with these concepts in FreeCAD right now. So far I am focusing on individual parts. But at some point I will want to model several parts in one file. That should be in the first hour of instruction. Having used Fusion I want to start my models with a parameter list. I have learned that one way of doing this in FreeCAD is to use a spreadsheet. That seems a bit cumbersome after Fusion just automatically having that list available and ready for my editing. But I still don't know if the spreadsheet is saved in the part's file or in a separate file. And just how does the spread sheet work? My present impression is you must refer to a name assigned to the cell that contains the value. And prefix that with the name of the spreadsheet. New question, can I have multiple spreadsheets in one part model? Otherwise, why would the name of the spreadsheet be needed? Perhaps there is a way to declare a universal spreadsheet in a model? And then only the cell name would be needed. Or perhaps not. That is something that should be covered in the first hour of any instruction. And many other details of just how the 3D CAD program ACTUALLY WORKS. I am sure the ling time users who already know the answers to these and other foundational questions will dismiss these concerns with a wave of the hand. But it is the lack of details like this that make learning a new program difficult. And error prone. So that is my advise to someone making the tutorial videos. START WITH THE BASIC BASICS!

I've tried a number of CAD programs. There's a vast disconnect between the way their programmers expect a drawing and an object to be created and how an experienced design engineer does so. They're far too pedestrian and inhibit creativity.

I'm a Solidworks user and I never use a face as a reference plane. I also try my hardest to never create new planes. I usually work off a Skeleton model that only contains sketches and they are mostly referenced to the top, front or side planes. Things stay much more stable this way especially when you have many parts referencing the skeleton model

Thanks! Can you suggest the way of creating helix shape with different angle at start and end of it? Current hellix menu have only pitch, 1 angle, radius and height options.

Is FreeCAD 0.20 Broken? Find out here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-U6W0ipxzKBE.html A huge thank you for all your comments and I love to read through them all! (So keep commenting I love to know your thoughts on this) For the time being, I have gone with the majority decision of starting a course with Real Thunders Branch: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-p_ZEry2wTfg.html Once freeCAD updates I'll also be making a new course then. And don't worry you hardcore veterans and engineers my plan is to teach the basics first and then I'll show the origin and datum plain referencing workflow.

I'd go with realthunder tutorials and the crossover, thanks for the videos

Fully agree on calling that a bug. I started teaching myself CAD with FreeCAD (bacause it's free) after seeing that it comes with all bells and whistles. Now, I got me that bloody nose and it took me some time to "understand" that bug. I'm still scratching my head when thinking about having a sooo sophisticated program having such a basic design error. Still cursing when detecting that I have to make a correction in one base sketch and knowing the whole lot on top (or parts of it) will likely break :-(

The topological naming bug in FreeCAD seems to be a fundamental flaw preventing sketching on faces, which is easy to do in most all other CAD software. The work around seems to be to always create a datum plane equal to the face. If this is true, the fix for this problem seems relatively easy. FreeCAD has to know the size, location, and orientation of a face. As soon as the user selects a face to sketch on, FreeCAD should AUTOMATICALLY create and generate a datum plane on the face, BASED ON ORIGIN as opposed to face, which automatic datum plane is left permanent and independent of the face unless the user deletes the datum plane, whether the face changes or not. All relevant sketching seemingly done on the face is actually done on the datum plane, which is dependent on origin, not face, which was originally used to define the datum plane. These are the steps done manually to work around this problem - why can't FreeCAD do this internally automatically ?

Subbed! I have been using FreeCAD for a few months now, recently encounted the naming topology bug. I didn't know what to do for a long time and most of my stuff isn't super complicated so i deleted the bugged sketches and re-drew it on the face. Don't ask me what to do till 0.2 comes out your the expert you tell me what to do 👍

IHi there all, I'm at present just starting with Freecad version 0.20. Being fully versed in Rhinoceros3d, I never had this problem before. Now I wonder if I'd better go with the Realthunder version. Has this issue been adressed yet in version 0.20?

I am a newcomer to 3d, and would really enjoy in depth explanations on how CAD software functions and how to overcome the mentioned issues, even if the videos would be oudated in some time. But then again i totally understand that you would not be interested in spending the time.

I'd like to know, is it possible to use the RT version until FC 0.2 comes out and then move the projects to FC 0.2, or will that cause some compatibility issues?

Oh, thanks for pointing this out. As someone who does some CAD and a bit professionally, I'd like to learn the beginnings etc, but also dive deeper. So I guess the real answer is BOTH, sort of. If the new system is being pulled, to the main branch it seems it's a matter of time to hit the street. Also everyone would benefit from some (a more or less little portion) more in depth videos. I'm sure advanced and advancing users would HIGHLY appreciate this, as would I.

This is a major roadblock to Assemblies, as well. The most useful application of Assembly (as in SolidWorks), is to rough out ideas for each part, assemble them, then iteratively refine and correct them as needed. But as soon as you edit a part in FreeCAD, all the face names are scrambled, and the assembly relations are horribly broken. It is EXPECTED that assemblies will reveal changes that need to be made. That's kind of the whole point of CAD-to be able to discover and correct design problems in software, where it's easier. Without a robust and reliable Assembly platform, it will not progress beyond an interesting hobby tool.

I have had this happen to me a lot. As you mention I have to reference everything to the origin. It gets very tiring. I thought it was just me. Now I know why some of of parametric files fail. Thank you! I agree. Freecad is an awesome software but when you get to a point where you need to make things on the fly this definitely causes me great headache.

Hi Having been on the same freecad learning journey I two have had the same issues with sketching on plains, For me it manifested itself on sheet metal where I wasn’t able to sketch on a face created by the sheet metal bend function.

Wow. I tried to teach myself FreeCAD when my educational license for Fusion ended. I came to the conclusion that FreeCAD was unusable (to me) because I simply had no idea this was an issue and didn't stumble upon it this knowledge early on. If I had known this was the reason at the start, I likely would have stuck with it. I'm going to give it another try. I had no doubt it was good quality software, I honestly thought I was just terrible at CAD. I'm a software engineer by trade and have no professional experience in CAD though I have familiarity with modelers.

Thanks! I noticed this "bug" and was bitten by it some time ago. When I go back in the operations history of a part and edit something, the part breaks. I thought one solution would be for FreeCAD to restore face names after any edit by comparing actual geometry so that same actual faces keep their original names. I'm looking forward to some solution to the problem.

This one has been there forever. Then in v19 they broke the parametric equation editor, so it can't give a list of field names. So parametric CAD with wonky equation editor and the shape naming issue. The more you are in it the more you will curse, but it is free and works enough to be useful. But when it breaks, wow, painful.

I think I ran into this after about 30 minutes in FreeCAD, it made me really not want to bother learning more of the software. If Fusion360 wasn't actively trying to drive away all of the free hobbyists I would probably have stopped completely.

I would like to follow your freecad videos. I do not see a freecad playlist. You have much content, thank you, but a point of entry will help newcomers. This video helps me see the issue. I have a lot to learn before it will limit me.

Being only a couple of months into FreeCAD, I know this problem all too well... Despite using RealThunder's branch, I still end up creating a save file everytime I add a layer (sketch, pad, pocket, etc), because many-many-many times, I need to go back to one of those steps and start building up again because things break easily when I tweak something and half my model might suddenly no longer render... It's super frustrating, and I wish it weren't the case because I do quite like what it has to offer and I have perservered to make some really cool 3d-printed parts with it.

I used Catia for the last 20 years, and Catia let one not use scketches if you choose not to. I never used a scketch to avoid the type of problem being talked about. I would put a point in space, and would attach geometry to the point, create a surface, turn the surface into a solid and have a very stable parametric solid part. Is this possible in freecad?

Interesting video. I came across it in my frustrated attempt to find information about links going out of the allowed scope when fusing in FreeCAD. Have you experienced this and if so, do you have a suggestion on where to go find answers on how to fix it? I believe that the link error is causing problems in my 3D printed parts, as there is a seam that keeps appearing where it shouldn't.

I've mainly only ever used 3d modelling programs like Blender. I tried to learn Fusion360 and FreeCAD but the workflow is a bit confusing and the tutorials I followed were just as confusing. You said one thing that the tutorials failed to mention, or maybe they just didn't say it in the right way... each face can be a plane for a new sketch. I hadn't thought of it that way before, but it makes so much more sense now! It's a bummer about the sketches being linked to the name of the face, though.

Problems like this made me stay with Fusion 360, even after the license change...

I have a completely different suggestion: double down on Blender. Most people using Blender love the open source nature and CANNOT use Fusion360 (for whatever reason). Also Blender is more powerful then Fusion in many areas. I would suggest you pick some of the best beginner/advanced Fusion360 tutorials where they create simple parts. Then you use Blender to imitate the tutorial. I actually did that with a Fusion tutorial. At first I was annoyed but I learned so much: 1. sometimes very similar solutions exist in Blender (which you wouldn't have found otherwise) 2. sometimes you do it completely different (the Blender way) 3. often you do a combination of 1. and 2. 4. modifierers, modifierers, modifierers: you often build entire objects just using modifiers. Therefore fully parameterized! Maybe in 12-18 months FreeCAD has gotten it ironed out. At the moment its not worth learning stuff that might change in a few months. I also sunk almost a week in FreeCAD. I love it but hate it more ;) It's worth having your own niche...something like: show people how Blender can be comparable to Fusion360 in many cases.

This video helped me a lot. Thanks man. Have you ever encountered other pronlems or some like I had? I knew about this but in my opinion it is not even that bad. Worse is when you spend over 10 hours and you do finish your very complex model that NEEDS TO BE SPLIT which can be only done by boolean operations in PART (that is like the most buggy thing in galaxy) and you realise you can't after literally trying aroud 4 ways to do just that. There is a way that would work but it would take longer than redesign the whole thing from scratch namely cuting every single body individually and then exporting 3d model.... and on and on. FREECAD IS THE BANE OF MY F..ING EXISTENCE. Well sometimes it is but I will only use the datumplanes to origin way of doing things. That definetly will help, because I think my problem here is that I used CROSS REFERENCING between different bodyes and parts like a milion times and freecad USED TO CRASH from that. It even says that I have cross refference cycles. I was trying to copy my thing 3 times and boolean cut it up to 3d printable parts that would be later 3d printed obviously and assembled irl...

Instead of a sketch on a datum plane, you could also sketch on a default origin plane, and then go to the Properties View of that sketch and modify the Attachment/Position/z value so it aligns with the face you like to feature. Combining this with wiring up a spreadsheet for your critical values, gives a lot of freedom.

Despite the no doubt wondefull work of the 'thunder' developer,whom I greatly admire', I will keep on using the official release as I absolutely believe the problem will be solved in a next release. Also the original initiative of this wonderfull software is what I would like to keep supporting for the moment. I am a long time AutoCAD user and Fusion360 (done lots of work in 3D-studio in the past as well.) I hope the thunder developer and the freeCAD dev's will keep an open mind about cooperation.

Your concerns are spot on but Freecad already a fundamental problem with its terminology, which makes it far less intuitive than other software. Coming from an FEA background I expected it to be easy to pick up but the last three weeks of me trying to adapt to it have been incredibly frustrating. It is a pig. Perfectly capable but because it has grown with contributors each having different ideas, it has become an overly complex monster that has a steep learning curve regardless of the bugs, once the user starts to push beyond simple sketches and models. I'm sure that many power users love it because of its flaws and nuances but I doubt most users will ever get to that stage.

Im so glad I noticed mentioned issues after few days of using FC, I almost throw it away and Im way more glad I do not need to wait for fix or hearing "there is way around, then its not mandatory to fix" that i heard at many open sources projects after reporting some issues.

Why doesn't allow FreeCAD Spreadsheet cell referenced Math in the Spreadsheet itself? I can't perform any Math in it. For example, if I type this in Excel "=A1+ B1" in Cell A2 then I get the result in that cell. If I do that in FreeCAD Spreadsheet, it just writes the formula in the Cell A2. Is there a workaround to force it to do Math? Edit: it performs a bit differently and not so intuitively than excel... what a bummer -.-

I moved from freecad to fusion 360. fusion has a very gentle learning curve...I'm loving it...and you have the free interface. Very happy now.

Nice video, just a question (way too late), if you reference the edges to a point (lets say 5mm to the left and 5mm to the top) would this happen?

Minor correction, it's FreeCAD 0.20 (o point twenty) the version number is not a decimal but a MAYOR_VERSION.MINOR_VERSION naming scheme so trailing zeros should not be omitted. FreeCAD 0.2 came out a loooong time ago.

You should definitely teach FreeCAD as it works currently. And I wouldn't wait for some upcoming release. For one thing, older versions of FreeCAD are going to stick around for awhile as the official packages in Debian Stable, and Ubuntu LTS, etc. So people will run into this issue for a long time after it is fixed. The skeletal geometry approach is worth understanding, and I think leads to more robust parametric models (that are less likely to break when parameters change). Even commercial CAD packages are not perfect at dealing with changes deep in the feature tree / history, and you often have to spend more time fixing up sketches and features than it would take to delete the features and start over.

Yes, I came to the same conclusion. Broken. I found there was little consistency between the UI for different menus. Its as if 20 different menus were written by 21 different coders - each with their own interpretation of how the UI should work. It looks great from the outside until you start trying to do something real with it. Openscad (Parametric CAD) is far more useful productive and consistent. You code up what you want the package to do. I also using Blender 3.1 and settled on that

You nailed it, as always. It's not a "problem." It's a breaking bug! I am not going to waste any more time with FreeCad until it's stable, and I wouldn't expect that you would either. (And I have to ask: Wikipedia says that FreeCad has been in development for 20 years. So how is it that it has such a seemingly fundamental bug?) Edit: I guess I'll give FreeThunder's branch a try... Joining you over on your FT tutorial. Thanks again for the great videos! :)

Thanks for the explanation. Used to program cad programs as a day job. Nothing easy about it. I would tend to agree with you on the dont put out vids that may be obsolete tutorials in a few months time. My take on this would be make new tutorials using the thunder branch clearly prefacing the video with the fact its not the official branch and link back to this one to explain why. You should try a few complicated workflows in both version and film them with snagit (whatever screen cap soft you use will do). Maybe diff the resultant step files to check how they differ between the official and thunder branch. (I suspect thunder may do this themself). Dont give up on freecad its so powerful and our best chance of preventing complete comercial dominance of fusion and solid worx from being the only options and not having cadcam being only sas. Also by doing all your workflows twice in both apps you make find thunder some bugs they have missed or conversely help freecad to implement the right fixes back into the official. Hard work but thoroughly worth it if you can get freecad official back on track.

I've been thinking about switching from Fusion to FC but then I came across this video. It's now two years old- has this issue been fixed yet?? This would definitely be a dealbreaker for me.

Is it available for Windows? I tried looking for a version but I was time restrained at the moment.

It is not good practice to use surfaces as reference planes, you should use datum planes for this purpose as it can cause issues with complex designs even though it works in NX /SW / Caria. You should teach the use of origin and planes as references as this is often required in large company environments

Its good practice to use parameteic reference planes rather than body features so it's not really an issue. This same "issue" occurs in professional and very expensive software too.

If you think that Datum Plain workflows will still work in future versions, it would be useful to have them. If it's a good practice across any CAD platform, it's a good thing to teach and a good thing to learn. If a quick and convenient shortcut (building off of faces) comes along in a form where the software does a decent job of protecting a user from their own poor CAD practices, that's fine, teach it when it arrives.

First of all - the presentations you have made (both for Blender and FreeCAD) are excellent and a joy to follow! Having viewed FreeCAD content from others, I became aware of the Topological Naming Problem (TNP). My approach has been to set this issue aside and use the available time to learn about other features and methods. Currently, the newbie may choose to watch videos that describe the TNP and how to fix it, tutorials bug workarounds, or use the RealThunder branch. In my opinion, your efforts should be better spent on continuing to produce content that has great value to the CAD/3D community by circumventing the issue for the time being and allowing the TNP developers to find a solution to their buggy code - which might be achieved within the next 6 months. The suggestion by Lewis Cobb in the comment section to bring enthusiasts up to speed (with so much more to learn) is probably the best option. Having skimmed through the TNP, my reaction is that the learning curve is already steep enough and that delving into the intricacies of the TNP bug is not worth the muddle when solutions are within reach.

I had trouble getting references between parts, that was the reason why I quit using FreeCad. If I knew how to do that I would be willing to give it another go.

What i noticed about working around bugs in FreeCAD is the new way was a better way to go about the problem.

Still happens I just started three days ago and ran into this problem. Also how come if you want to edit or sketch to a face it doesn't recognize the borders of said face. *I got around the problem by restarting the whole project luckily it was small

Sadly, FreeCAD 0.19.2 for Windows seems to be broken overall. So much so that I dropped back to 0.18, after going to save a document I was working on for an hour only to have it crash (then no recovery file was made even though it was set to autosave every 20 minutes). Also there were problems I was having in my workflow in the Part Design workbench. Sketches that used to work in 0.18 would give me "invalid face" errors in 0.19.2 (draw a square in a square then a circle for a hole inside the inner square and try pocketing that sketch). The naming issue has always been a pain and I used to have to break my models down, re-map the sketches to the correct faces and then continue on. Something a newbie would probably get totally lost in the tutorial. Didn't know about RealThunder's branch. May try that and hope it is a patch until 0.20 comes out (which is usually a year after they get the Linux version stable). Thanks for this video.

i was just starting to learn freeCAD and then i saw this video, and im so glad i did because i was wondering about this problem, having encountered it myself. I think im just going to keep using the free version of fusion until they fix this.

I wanted to CAD for the first time since switching to Pop!_OS Linux. Today, I tried 3 ways to run Fusion 360, and failed. I gave up and opened the STEP file in FreeCAD. I don't CAD much. Now I have to learn. I wanted to put off learning.

What you'd like to achieve is parametric design. Fusion covered the most of it through it's history bar, while construction in other software requires more primitive geometry built to define points, planes or axii to define a sketch.

@Maker Tales 0.19.3 is already out (since 13. Dec 2021). Does it have fixed the bug?

I have spent a lot of time learning Blender. It's an amazing product and your videos have been a great help, so many thanks for that. However, I have been struggling to find a way of printing simple objects in 2d to scale. I thought Freecad might be the answer and I was looking forward to your tutorial series, but now I am in doubt. I really don't want to spend a lot of time learning a program with a serious bug and I would rather put the effort into Blender. I think it would be best if you hold back on the Freecad tutorials until it is fixed.

And a year later, 0.2 is out, and no joy. So sad. Meanwhile, more and more people are moving to the RealThunder branch. Not a good sign for the official open source version. Why isn’t this priority #1? Amazing.

I always wondered what the hell kept causing this to happen. After watching this now it perfectly describes the issues I've been fighting.

Great video! I am looking for the good CAD program for my channel, which works on Mac. Unfortunately it does not exist.

At a company that takes cad seriously you wouldn't be allowed to draw straight on a face due to this "bug". Makes the model as stable as a house of cards in a 100km/h storm for future changes.. Just use planes to drive the model and problem goes away...

WOW! Everything I wanted to say and more! You hit the nail on the head with this one. I’m afraid the problem is all of those options are bad. Really if you stick to the last “LTS” FreeCAD but make people aware of these problems your videos will stay relevant longer. I have always hated watching a tutorial just to realize half way through everything has changed or I had a different distro/version. That’s what would happen if you used the offshoot version. I have also struggled with this bug. I love FreeCAD but I have lost some hair trying to fix broken models after it scrambled all my bevels to random edges because I changed something in a lower level or moved shapes around. Really I don’t see how each edge and surface doesn’t get a random hash assigned to it that works as it’s name as long as the part is in existence. Add a surface, add another hash preserving the existing hashes etc. Good luck!

I learned to live with the topology naming bug, but its a pain. I have problems when I design a project with multiple parts. I have trouble fitting and aligning the parts and transferring feature locations between the parts. Usually at about 5 - 10 parts I go to Fusion 360. I hope FreeCad fixes the topology naming issue.

Seems to be a persistent problem in the open-source world. The software is written by the users, but since they understand it from the inside out, they aren't motivated to fix the problems that new users see from the outside. In some cases it seems they relish that people find the software impenetrable. I haven't yet jumped in to freeCAD, because it does seem to suffer from this problem...

my memory may be faulty however, about 35 years ago I came across a reference to this in some of the early work of creating an ISO standard for the referencing of solids in a portable file. The proposal was that all the solids in a model were referenced by the origin and direction of the solid to 0,0,0. Hope this helps !

so true. I am mechanical engineer and open source enthusiasts but I never could make it with freecad. Thanks for this explanation

I have the same problem with FreeCAD and since I often do concept work, where almost everything is parametrized over a spreadsheet, this breaks things regularly. But my primary problem is speed and Boolean operations for example for ring gears. I just have to wait minutes to make single change in a spreadsheet for a kind of a planetary gear system that is fully parametrized. There are further often other bugs, so I am learning blender now. I think that blender given its age has probably a much faster backend ... and I can do nice animations for concepts!

This bug is the main reason why I haven't switched from Fusion yet. It just fundamentally breaks the software

I had the same issues in Inventor, up to inventor 9 included, than they were corrected such as in Inventor 12 almost everything was OK, (I was a heavy user of Inventor, some 200 to 300 hours a month for years) I see them in FreeCad too, not only the one you pointed out, also the fact that given an exitant body, let say I want to create a special shape hole in it, so I make another body to run a boolean extraction leaving the cavity desired, as long as it is in one piece, but if I need two or more holes than FreeCad would not allow me to even extrude two not connected objects of a single body so I can than run the bolean operation, nope, I have to do them exruding one body, run the boolean extreaction, than make a second body, and so on. The other "obvious" solution, performing the single object body extrusion plus boolean operation than creating a pettern does not work either, full of flaws, and don't make me started on patterns here... they suck like hell even if only compared with Inventor 9 edition.