Frequently asked questions/fr

Cette page tente de répondre aux questions les plus fréquemment posées sur les forums FreeCAD.

Si vous avez un problème ou une question concernant FreeCAD, vérifiez ci dessous avant tout. Puis, si vous ne trouvez pas de réponse à votre question, allez voir et au besoin poster sur le forum de FreeCAD !

Quel est le moyen le plus facile, pour installer FreeCAD sur mon système ?
Si vous êtes sous Windows ou Mac OS, le moyen le plus simple est de vous rendre sur la page Téléchargements, où vous trouverez plusieurs packages prêts à installer. Si vous êtes sur Debian, Fedora ou Ubuntu et d'autres distributions, FreeCAD est déjà inclus dans les référentiels de logiciels standard et vous pouvez simplement l'installer avec le gestionnaire de logiciels. Sur Ubuntu, l'équipe FreeCAD maintient également ses propres dépôts PPA. Pour plus de détails sur l'installation, reportez-vous à la page d'installation de votre système d'exploitation (Windows, Linux ou Mac).

Quelles sont les conditions requises pour l'exécution de FreeCAD ?
Contrairement à la plupart des logiciels de CAO 3D, FreeCAD peut fonctionner correctement sur les ordinateurs les plus modestes - il est connu pour fonctionner sur les processeurs Pentium IV et Intel Core2 Solo. Si votre ordinateur exécute un système d'exploitation récent, il y a de fortes chances que FreeCAD s'exécute. La seule condition préalable est que votre carte graphique ou chipset prenne en charge OpenGL, de préférence pas plus ancien que v2.0. En cas de problème, reportez-vous à la section Dépannage de cette FAQ.

Multithreading
Le noyau de modélisation géométrique sous-jacent de FreeCAD, la bibliothèque tierce Technologie OpenCASCADE (OCCT), ne prend en charge que partiellement le multithreading pour le moment. Voir la page multithreading pour plus de détails.

Pour les utilisateurs Mac
Seulement l'architecture MacIntel est prise en charge. Il n'y a aucune version disponible pour l'architecture PowerPC.

Que faire si je veux compiler FreeCAD moi-même ?
Le code source de FreeCAD est toujours disponible dans le répertoire du code source du projet. Compiler vous-même avec FreeCAD vous permet d’utiliser les dernières fonctionnalités en cours de développement mais nécessite quelques connaissances informatiques, bien que la procédure soit relativement simple. L'accès au code source est expliqué ici et ici des instructions détaillées pour la compilation sur Windows, Linux et MacOS.

FreeCAD me signale que certains modules ou applications sont manquants
FreeCAD dépend de beaucoup de choses pour offrir toutes ses fonctionnalités. Tous les principaux composants requis sont généralement regroupés dans votre installation FreeCAD ou fournis par votre gestionnaire de packages, donc normalement vous n'avez pas à vous inquiéter. Cependant, si vous avez installé FreeCAD à partir de sources non officielles ou compilé FreeCAD vous-même, une partie peut manquer, ce qui n'est pas critique pour FreeCAD lui-même, mais peut entraîner l'indisponibilité de certaines fonctionnalités. Certains formats de fichiers spécifiques tels que Collada ou DWG nécessitent également des composants supplémentaires, qui ne peuvent pas être regroupés dans FreeCAD, et doivent être installés par vous-même séparément.

Tous ces composants et la manière appropriée de les installer sont listés sur la page Modules Python supplémentaires.

FreeCAD ne démarre pas du tout
Il peut y avoir de nombreuses raisons à cela, la plus probable est que certaines bibliothèques sont manquantes. Essayez de démarrer FreeCAD à partir d'un terminal (saisir après le prompt,  sur certains systèmes) pour voir si un message d'erreur apparaît. Lisez aussi le reste de cette FAQ car cela peut vous donner divers indices pour détecter la cause du problème. Si rien n'y fait, parlez en sur le forum, il y aura sûrement quelqu'un qui pourra vous aider.

Sur certains systèmes Windows XP plus anciens, vous pouvez recevoir un message d'erreur comme celui-ci: La raison de ce problème est que sur votre système, soit les bibliothèques d'exécution CRT sont manquantes, soit la version installée est trop ancienne car FreeCAD était lié à une version plus récente. Dans ce cas, vous devez installer le que vous trouverez chez Microsoft. Voir aussi le message de forum correspondant.

FreeCAD démarre normalement, mais toutes les icônes ne sont pas affichées, certaines d'entre elles sont remplacées par un 'X' noir
Certaines parties de FreeCAD dépendent d'un module Python externe appelé Pivy. Sous Windows, pivy est inclus dans l'installation de FreeCAD. Sur les systèmes Debian/Ubuntu, le paquet python-pivy fait partie des dépôts de logiciels standard. Sur d'autres systèmes, pour le moment, vous devrez peut-être compiler vous-même. Notez que bien que certains outils ne soient pas disponibles sans pivy, le reste de FreeCAD fonctionne normalement.

J'ai des problèmes d'affichage, la vue 3D ne se comporte pas correctement, il y a des résidus, trainées quand je bouge/fait pivoter la vue, etc.
FreeCAD dépend d'OpenGL pour afficher le contenu 3D et nécessite donc un environnement OpenGL fonctionnel. Sur certains systèmes, OpenGL n'est pas activé par défaut et vous devrez peut-être installer ou mettre à niveau vos pilotes graphiques. Ces problèmes surviennent le plus souvent sur les systèmes Linux ou sur les systèmes virtuels. Si vous utilisez un système Linux, essayez les étapes suivantes:
 * vérifiez que votre ordinateur dispose d'une carte graphique compatible 3D
 * tapez dans une fenêtre de terminal, et vérifiez dans la sortie que Direct Rendering est réglé sur "yes" et que le fournisseur/moteur de rendu/version d'OpenGL correspond à votre carte graphique.
 * installez un autre logiciel basé sur OpenGL (Blender, par exemple) et vérifiez s'il fonctionne et s'affiche correctement.

FreeCAD plante au démarrage
Un plantage peut indiquer un bogue plus grave ou un problème dans votre configuration. La plupart des plantages au démarrage se produisent pour l'une des deux raisons suivantes :

Les pilotes OpenGL ne sont pas installés, ou ne fonctionnent pas correctement
C'est une cause très courante du problème. Les symptômes sont simplement que FreeCAD se bloque au démarrage, ou chaque fois que vous ouvrez une vue 3D (par exemple en créant un nouveau document). Essayez de découvrir quelle est votre puce graphique, puis découvrez si elle prend en charge OpenGL (les puces les plus récentes le font), puis trouvez le pilote approprié et installez-le. Un bon moyen de vérifier si OpenGL est disponible est d'essayer d'exécuter une autre application OpenGL telle que blender.

Et comme astuce générale pour obtenir plus d'informations sur les plantages avec FreeCAD, vous pouvez le démarrer avec le paramètre de programme. Cela créera le fichier dans  sous Linux et Mac OS X ou  sur les systèmes Windows.

In some rare cases you may have a graphic driver installed that doesn't fit to your graphic card. We had a case where the user's laptop had an Intel on-board graphic but some ATI drivers were installed.  After removing the files and re-installing the correct driver FreeCAD started to work.

Some library, needed by FreeCAD, is not present on your system, or wasn't found by FreeCAD
There can be two paths to this problem: either some library is simply missing, therefore FreeCAD will refuse to start, or the library is there, but it is an older version than the one FreeCAD expects, so a crash will occur when FreeCAD attempts to use a missing feature from that library. A common example is when you have Qt3 and Qt4 installed on your system, FreeCAD might detect Qt4 but if your Qt installation is not properly configured, some pieces of Qt3 might still be used, provoking crashes.

Please review the installing procedure (Windows, Linux or Mac), make sure you installed all the required libraries (on most linux systems this is done automatically), and check what is the minimum version number for each of the components.

If everything seems correct, describe the problem on the forum or submit a bug. If you are on a linux system, it is easy to do a debug backtrace, which provides very useful information about the crash to the developers:
 * in a terminal, type: (assuming package gdb is installed)
 * inside gdb, type
 * after the crash, type to get the backtrace, that you can include in your bug report.

FreeCAD freezes after startup
When starting FreeCAD the GUI appears almost immediately but the GUI is frozen and the cpu is about 99%. This can happen on the KDE desktop when using the Oxygen theme. That's a bug in the Oxygen theme and choosing another theme should fix this issue.

FreeCAD crashes on creating a new document or opening a file
If FreeCAD crashes when it creates a new 3D view, try launching FreeCAD from a terminal. If a message error appears when the crash occurs, mentioning, and a component name beginning with "So" (, , etc.), the chances are very high, especially if you are on Linux, that FreeCAD is trying to use two different versions of the Coin library, which causes the crash. To verify if that is indeed the problem, try the following: If there is any difference, either FreeCAD or SoQt must be recompiled (better to recompile the one that uses the oldest Coin version). The normal behavior is to try to contact the people responsible for packaging either SoQt or FreeCAD and kindly ask them to consider recompiling. If you want to undertake that step for yourself, and it is not possible to recompile SoQt because it breaks other applications on your system, you can force FreeCAD to compile with the required Coin version with. But you have to make sure that the correct development package of this Coin version is installed.
 * Locate the FreeCAD executable (usually in )
 * Run the command from a terminal
 * Note down the version of the library that FreeCAD is using (for example )
 * Locate the library (usually in )
 * run and check if it links to the same Coin version as FreeCAD

FreeCAD crashes after Edit → Alignment
A segmentation fault happens at. This means that the implementation of VBO in the graphic driver is bad. In order to avoid caching OpenGL calls you can try to set the environment variable and restart FreeCAD.

I have trouble running FreeCAD on Mac OSX
The Mac platform is less easy to support than Windows or Linux, since none of the core developers owns one. The OSX packages are compiled by volunteering FreeCAD users, and they might sometimes not work correctly on your machine, depending on your system. Your best chance is probably to head to the forums, look for Mac OSX-related threads, and discuss your problem there or see if someone else encountered a solution.

I cannot change numeric values in FreeCAD's properties panels


You most likely have bad windows regional settings set-up. Please check if you have the same symbol for decimal separator and digit grouping symbol in your regional settings. If you do, adapt your system settings to use different characters for the digit grouping symbol and decimal separator. Note that it is not mandatory to have dot as decimal separator. It is mandatory to use different symbols in these two settings.

FreeCAD was running normally, and suddenly it doesn't start anymore
This can also happen if you had an older version of FreeCAD installed, and you upgraded to a newer version. In that process, the configuration files of FreeCAD might have been corrupted for some reason, and now FreeCAD cannot read them anymore, and fails to start. The solution is simply to delete these configuration files, so FreeCAD will recreate them on first run.


 * On Windows: Open the file explorer, and write as the file path. Once there, delete the files  and
 * On Linux: Navigate to and delete the files  and
 * On Mac: Navigate to and delete the files  and

FreeCAD should now start again normally with all its settings reset.

There is a Macro findConfigFiles available to help in locating your configuration files. It can be installed using the Addon Manager in the Tools menu. . The macro will find your config file folder, copy it to the clipboard, and (attempt to) open that location with your default file browser. It makes no changes to your files or settings.

Is FreeCAD really free? Even for commercial use?
FreeCAD is open-source software, and is free not only to use, for yourself or for doing commercial work, but also to distribute, modify, or even use in a closed-source application. To summarize, you are free to do (almost) anything you want with it. See the Licence page for more details.

How do I rotate the 3D view?
FreeCAD has several different navigation modes available, that can be set in the preferences settings dialog or changed by right-clicking in the 3D view. For full details about the modes, see the Mouse Model page. For the default mode ("CAD Navigation"), the commands are as follows,

What can I do with FreeCAD? Where do I start?
Head to the Getting started page for a quick description of the tools you can use. There is also a new Tutorials section containing a few resources. The User hub section contains more detailed information about the different workbenches of FreeCAD. Note that since FreeCAD is relatively new, its user interface is still very bare and doesn't feature many tools. But much more advanced functionality is already available to you from python scripting.

Is there documentation for newcomers? How can I learn to use FreeCAD?
There is a lot of documentation spread in different places, both on and outside the FreeCAD website. You might want to start with the Getting started page. The Tutorials section contains many specialized tutorial pages to help you getting started with the different workbenches. The Manual is a general, complete user-oriented guide to FreeCAD. The User hub section of this wiki lists all pages aimed at end users. On external sites like Youtube, you will also find a load of video tutorials created by users. And, last but not least, the forum contains a lot of replies to questions asked by other newcomers.

I want to import/export data in format XYZ to/from FreeCAD. How do I do that?
Please refer to the page FreeCAD Howto Import Export. Maybe your questions are already answered there.

How do I extrude stuff into solids? I don't get the right result
The theory is simple: Lines (or wires), when extruded, form faces. Faces, when extruded, form solids. If you extrude something and the result is not a solid, then the something was not a face. If you have lines and you want to extrude a solid from them, you must first select lines that form a closed perimeter (select several objects by pressing ), join them into a wire (Upgrade tool), then make a face from that wire (Upgrade tool again). There you are, if all went well you can now extrude it to a solid.

Now, there can be many little twists that make you obtain the wrong result. The best way to make sure is to check what's inside the object you are extruding. Objects contents can be easily explored with python. Assuming for example you have an object called "Wire", you could type this into the python console:

The above code retrieves the shape from an object, shows the faces and wires your object has (if any), and, if there are wires, prints if those wires are closed. If you don't have any face, you won't get a solid. If there is no closed wire, it won't become a face. If you are interested, there is more info about what you can check with python on the part scripting page. If you cannot join several lines into a wire, the most probable cause is that their endpoints don't meet, there must be small gaps between (some of) them. There, I'm afraid, my experience tells me the quickest way would be to redraw a wire on top of them.

My boolean operations fail, or give weird results
The Open CASCADE geometric modeling kernel used in FreeCAD for Part geometry, although probably the best open-source geometry kernel available, has its flaws and limitations. Indeed the boolean operations (fusion, subtraction, intersection) are not its best features, and often give strange results. This is a current limitation we have no way to solve at once, so your best path is to try obtaining the desired result by modeling another way. For example, problems with primitives such as cylinder can often be solved by using an extruded circle instead. Coplanar surfaces between parts can cause trouble, as well as surface tangency. As a general rule, if a shape doesn't work, try remodeling it a different way. In 99% of the cases at the end you will manage to obtain the result you want.

When I export (or view) my model, the holes are filled in
Don't use +  (Select All) to export everything from the hierarchy tree. If the model is of one single item, try selecting only the newest item (usually the last one) in the hierarchy tree.

As we create a model in the PartDesign Workbench, each feature takes the shape of the last one and adds or removes something, creating linear dependencies from feature to feature as the model is created. Hence a "Cut" feature is not only the cut hole itself, but the whole part with the cut. This is why the user usually should only have the newest item (feature) in the model tree visible, because otherwise the phases of the model overlay each other, and holes are filled in by the earlier model features.

To toggle visibility of an object on or off, select it in the hierarchy tree and press on your keyboard. Usually everything but the last item in the hierarchy tree should be greyed out and therefore not visible in the 3D view.

My parametric objects break when I modify their base sketches
You have met the (in)famous toponaming problem. This is currently a major issue in FreeCAD for newcomers. It is present all over FreeCAD, but is more prominent when using sketches. The explanation is simple: When recalculating a sketch, the geometric entities (edges, faces...) are rebuilt in a different order, depending on the constraints precedence. They then receive a different name (Edge1, Edge2, Face1, Face2...). Most subsequent operations depend on these names to identify which subcomponent they work on. Therefore, when the sketch is rebuilt, features that are based on such subcomponents might suddenly get their base geometry changed and give a wrong result.

This is a very hard problem to overcome (the Topological Naming Project aims at solving it). However, there are many workarounds available to mitigate the problem, and more advanced users generally manage to avoid it completely. A couple of strategies are:


 * Know that sketches are highly sensitive to the problem. Referencing a specific edge of a sketch, or a face of an object built on a sketch, such as a PartDesign Pad, is dangerous, unless you are pretty confident that these sketches will not change over time or the sketch is very simple. A Pad built on a simple rectangular sketch, for example, will likely be safe as it will generate only one face, so there is no order problem.
 * Prefer other kinds of objects such as Part or Draft when possible. These objects are always built the same way, and therefore their geometric components usually follow the same order each time they are rebuilt. They are much less susceptible to toponaming problems.
 * To attach further objects onto the faces of sketch-based geometry, prefer using Datum geometry. These invisible "helper objects" don't depend on sketch geometry, and therefore stay stable over time.

FreeCAD is such a great program! How can I help?
There are a lot of different ways to help, even if you are not a programmer. Here are a couple of things you can do:
 * Give some feedback to the FreeCAD developers: It is always useful to know what people think, what they found good, what they miss, etc. Drop a note on the forum giving your opinion or make a request on our issue tracker!
 * Help with writing documentation: The documentation we have here on this site is sometimes very limited. If you discovered something that is not well documented, add your knowledge there!
 * Help others newcomers: Hang around the forum, and help new people to solve basic questions, like how do I install, how do I add a cube, etc.
 * Translate the documentation into your own language
 * Translate FreeCAD into your own language
 * Write Tutorials, or record video tutorials: Tutorials are a very easy way for newcomers to learn a new software. If you did some nice stuff, why not show other people how to do it?
 * Contribute with assets and examples: We are still missing good example files in FreeCAD. If you created something good, share it with us!
 * Submit bugs: It is very important to have all possible bugs fixed. If you find one, report it as clearly as possible, so we can understand exactly what's happening.
 * Try to do some python coding: You never programmed before but you want to try? Python is easy. Read our introduction to Python, but beware, you might get addicted quickly!
 * See the Help FreeCAD page for more details on how to contribute.

How can I get edit permission on the wiki?
See the Work on the documentation page paragraph for more details on how to contribute.

Does FreeCAD participate in Google Summer of Code?
Yes. Beginning in 2016, FreeCAD participates in Google Summer of Code. See Google Summer of Code for information on past editions, and Google Summer Of Code 2016 in the forum for the original announcement.

I want to start translating the wiki in my own language. What do I do?
This wiki is hosting a lot of contents. The most up-to-date and interesting material is gathered in the manual.

See the Translate the documentation page paragraph for more details on how to translate the wiki.

Do I have to pay something to use FreeCAD?
No. FreeCAD is totally free to use, to download, to redistribute, or to modify. It is open-source software, published under the terms of the GNU Lesser General Public License 2.1, which guarantees you those freedoms and, even more important, guarantees you that these freedoms will never be taken from you.

Can I reuse any part of the FreeCAD artwork or pieces of the website?
Sure. All the artwork (icons, banners, etc.) of FreeCAD are licensed LGPL, same as the FreeCAD code. Help yourself on the Artwork page. The website is a standard MediaWiki site, all graphic elements can freely be reused, and if you are curious about how to tweak the MediaWiki software like we did, look for the special Common css and js pages.

Can I reuse pieces of FreeCAD in another application?
Yes, you can use the core parts of FreeCAD in other applications as long as you comply with the terms of the LGPL. Third party libraries, external workbenches, and macros may be subject to their own license terms, so please consult with their authors. More details on the Licence page.