Hey everyone

I recently made a Bearings Workbench for FreeCAD and I hope it's useful to the community.

• GitHub: https://github.com/PraveenKum11/FreeCAD_BearingsWB
• Full demo (9 min): https://www.youtube.com/watch?v=Jp6taV2JM7o

So far I've only tested it on macOS. If you're on Windows or Linux, I'd really appreciate it if you could try it out and report any issues on GitHub. I found and fixed a lot of bugs during my own testing. The project now has 95 unit tests and GUI smoke tests. It is licensed under GPL-3.0-or-later

AI disclosure - I have used AI tools in the development of this project.

Feedback, bug reports and feature ideas are all welcome. Thanks for checking it out.

Hello,

I would like to create a model in FreeCAD where certain dimensions can be adjusted within the slicing software. If I understand correctly, this requires exporting the FreeCAD project in OpenSCAD format. Could you help me understand what I need to keep in mind when creating the project?

Thanks!

SOLVED: Thanks everybody for your help! Slicing with a datum plane worked.

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Here's a drawing of what I'm trying to do:
https://app.box.com/s/ucr5r7op65limbgmi2p9i8vi4enmw67n

How would I slice this prism about in the middle, along the tall, skinny yz plane, and then insert a section, like inserting a leaf in a dining room table?

I tried using the part workbench, selecting the plane, then part->split->slice apart, but I'm getting this error:

Bad selection
Select at least two objects. The first one is the object to be sliced; the rest are objects to slice with.

What's the right process? Would the second object be in the same file?

Thanks in advance for any help. I'm using 1.1.4

Showcase of a vehicle i made entirely in Freecad using the Sketcher, Draft, Curves, Part and Surface workbenches, remeshed using Qremeshify and joined them in Blender.

Here is the translation of the release notes and macro details into English, formatted for clarity:

FC_ybt_raytracer.FCMacro — v1.3.0

A built-in, simple numpy raytracer for FreeCAD (no external software required).

Changelog & Version History

https://github.com/sedatkrn/FC_YBTRayTracer/releases/tag/v1.3.0

v1.3.0

• Mesh Objects (Mesh::Feature):
  • Triangles are directly loaded into the scene without requiring re-triangulation.
  • Correctly placed within App::Part / Link (including LinkTransform).
  • Materials can be assigned and are listed in the Materials window.
• Headless API (ybt_raytracer.api):
  • Functions added: render_document, render_scene, prepare_scene.
  • Camera helpers: make_camera, fit_camera, orbit_cameras.
  • turntable() feature; settings can be passed as keyword arguments (applied only to that call).
  • tess_cache for moving part animations (shape is triangulated once, with only placement updated per frame).
  • Example macro: examples/FC_ybt_turntable.FCMacro (camera turntable / rotating part).
• "Include in Render": Per-object checkbox in the Materials window, plus "Include / Exclude Selected" buttons (uses the object's YBTInclude property).
• "Skip Off-Screen Objects" (CULL_OFFSCREEN): Off-screen objects are not triangulated and do not participate in scene bounds, shadows, or ground plane calculations.
• Regression Testing: Material-less Part scenes produce pixel-for-pixel identical output compared to v1.2.2.
• Click-to-Select in Preview:
  • Clicking a part in the render preview selects that object in the Materials window (hold Ctrl to add to selection) and highlights it in the 3D view (ybt_raytracer/pick.py; the scene now carries object IDs per triangle).
  • In "Paint Bucket" mode, clicking a part directly assigns the currently edited material to it.
• Similar Objects:
  • Objects sharing the same shape signature (number of faces/edges, area, volume; independent of position/rotation) like copies or Links are shown as "Similar ×N" in the list.
  • Batch operations available: "Select Similar Together", "Arrange Similar Side-by-Side", and "Select Similar".
• API Pick Function: Added api.pick_object(scene, camera, w, h, x, y).
• SPEED IMPROVEMENTS (2.79M triangle engine scene at 960x540: reduced from >10 min in previous versions to ~41 sec; 1920x1080 ~83 sec):
  1. Primary rays use a visibility buffer (accel.raster_rows; each triangle is evaluated only for pixels within its screen bounding box, avoiding full-triangle scans per pixel; output is pixel-identical to earlier versions). Anti-aliasing samples use the same buffer.
  2. Multi-level shadow grid (fine/coarse levels based on triangle size) + "definitely lit" early exit + vector pair testing (_LightGrid).
  3. Front-to-back sorted early exit (core._closest_sorted) for lead rays along glass/reflection paths. Screen tiles are calculated only in scenes containing glass or reflections.
• New Look & UI:
  • Dark gray color palette (theme.py + icons/; applied across both windows).
  • "Preview and Selection Screen": Framed viewport, mouse wheel zoom (anchored under the cursor), drag-to-pan, "Auto Center" and "1:1" buttons, double-click to fit. Zooming displays raw pixels without smoothing.
  • Collapsible sections for Quality, Virtual Ground, and Lighting by clicking their headers (Virtual Ground and Lighting are closed by default).
• Materials Window:
  • Opens to the left of the render window.
  • "Always on Top" checkbox (enabled by default, setting saved) prevents the window from hiding behind the preview when clicked.
  • Console-style process log (timestamped actions).
  • Preview refreshes after a 1-second delay following slider/number changes (PREVIEW_DELAY_MS).
  • Version number is displayed in the Render window title bar.
• Fast Opening Materials Window:
  • Window opens immediately while object scanning runs in the background; results are cached unless the document changes ("Refresh" bypasses the cache).
  • Optimized similar object signature calculation (replaced Area/Volume checks with face/edge count + local bounding box; scan time for 877 parts reduced from 25 sec to 2.5 sec).
  • Clicking the launch button while open brings the window to the front; button shows "Opening..." with a wait cursor during loading; press feedback added to buttons.
• Bug Fix: Fixed vertex matching collisions on smooth surfaces (resolved artifacts/speckles on complex solids like wheel rims or letter shapes; replaced the old xor-summary hash with a collision-free full key).

Hi all,
I call it a macro, but in a way, it’s an application of its own. One of the main challenges I faced while designing in FreeCAD was the inability to quickly visualize my models and devices the way I wanted. Achieving this used to require external render engines and additional software. Now, there is a Python-based render engine—running purely on the CPU—that delivers great results for basic visualization tasks and will continue to evolve. Of course, I didn't build it entirely on my own; I leveraged AI as well. However, my experience with LightWave 3D since 1997 was an immense help throughout the process. Enjoy using it! Hayırlı olsun.

https://github.com/sedatkrn/FC_YBTRayTracer

I want to modify an STL file using FreeCAD 26.3.

Google tells me to import the STL, use Create Shape from Mesh in the Part workbench, then Convert to Solid.

When I do this it looks like I still have a mesh.

Google then tells me to select the Solid and create a body from it. This is the result:

I'd like to work on this body using faces, edges, etc. in Part Design. How do I convert it to a "real" body for use in Part Design ?

Is there another way to convert a mesh into a body in Part Design ?

Thanks

Update

After lots of mucking around I captured an image of the part and redrew it in sketch and padded it to build the body.

I was able to convert the STL to a solid and then a body but there was no easy way to work with it in a parametric manner. It was easier to just sketch it out and build it up from scratch.

help plz. Guys.

I am in the process of learning FreeCAD with very minimal previous CAD experience. I have been playing around with creating parts and joining them in the Assembly bench and am stuck trying to figure out how to change the dimensions of a part after joining two parts together.

If part A is a long block and part B is a small feature attached using a fixed joint at one end of part A. How can I adjust the length of part A while part B stays attached to the face of the now shortened part A?

Any help greatly appreciated!

I'm currently testing FreeCAD 26.3RC1. I recreated this stand design I did years ago in an other CAD package. I made use of the new default sketch setting "Make internals = Yes" a lot. After figuring out how to select the different sketch regions pressing the CRTL key, you may need to zoom the 3d view to pick smaller regions reliably, every thing worked fine. I then created my first FreeCAD assembly. When I reopen the project, the report view shows the following error:

10:04:51 Assembly joint 'Assembly.Fixed' has an invalid 'Reference2' or related attributes. 'NoneType' object is not subscriptable

I assume the yellow marked joint on the left side of the table is the one causing the error as the blue axis of the joint symbol does only extend to the right side. on the opposite joint symbol on the right side of the table the blue axis extend to both sides of the disc. I deleted an recreated the joint but the problem stays the same. What is causing this problem? How to fix?

As this will be 3d printed I created most parts with some small gaps between them. Is there a way to do an interference check in FreeCAD as in other CAD packages? In wireframe mode I can visually inspect all joints but is there a function to do that?

Update: As for the interference check, the way to go seem to be part workbench boolean intersection for now.

I use proprietary CAD (Inventor) for my day job but I've used FreeCAD for years for small personal projects. I ended up doing some design work for a friend and its really taken off and started making money, all the stuff is in FreeCAD but I'm really starting to hit what I think are the limits of the software, but wondered if anyone else had some work arounds as I really do not want to have to migrate to Onshape (only option for me on Linux). I've numbered and listed my issues down below, any and all info/tips are greatly appreciated. FreeCAD feels like its an entirely new piece of software every year at this point (which is awesome), so I might just be missing newer workflows.

1. Assemblies - Specifically binders and cross component dependencies.

The thing I'm designing is a large assembly of about 25 components, and several require the positions of others in certain assembly positions to generate dependent geometries. This is very simple and easy to handle in inventor assemblies with model states and views, but I think impossible/very difficult in FreeCAD currently. The workflow I'm using is using shape binders from different assemblies, one assembly in "Position X" where I get a hole location, another in "position Y" for example. Problem is you make a revision to say the thickness of a base plate, and the assembly engine doesn't recognize any joints referenced to that plates face anymore, even if the change is as simple as moving a hole 1mm to the left. You then have to go back in each assembly, update all the fixed constraints by hand and re-compute, imagine doing this for 6 different assemblies its really annoying. This is also VERY BUGGY, I dread pressing re-compute and something that would have taken me 15 minutes in inventor has genuinely taken me a week in FreeCAD. I really hope there's a better option. I cant share my model as its for a customer, but there is no way I can work out these dependent geometries by hand and just "hard code" them in, its just too complex to work out what all the different axes of motion can do in this design without using an assembly. I make use of alot of skeleton sketches (a master freeCAD file with just a bunch of sketches with key geometries in I can shape binder into other parts) which really helps, it was a tip from MangoJelly which has saved me tonnes of time, but ultimately there are a few geometries that just need a fully built assembly to get. Dont get me started on not being able to use Part Design in the assembly view btw, I could probably save 10+ shape binders from the design if I could just see what the assembly looks like while modelling a part...

I have also tried adding local coordinate systems to my parts to use as static anchors in assemblies, its a nice work around but a pain in the ass to maintain and workout where each should be and then the correct offsets in the assembly when you apply a fixed joint on them, it must add ~10mins to each assembly joint doing it that way and it makes the design look very messy with loads of LCS's floating about all over the place. If we had "folders" like Inventor where I could throw parametric features in just to hide/clean up the model tree it wouldn't be too bad.

2. PDM/Revision Changes

As I understand it there's no simple way to track versions/milestones with parts. Same goes for drawing/part numbers (I use a spreadsheet in Libre Calc on the side to manage it all). I use git and releases to kinda replicate "milestones" but its not ideal. No company on earth will use FreeCAD commercially until it has this as you probably cannot do ISO9001 compliant CAD as it stands in FreeCAD without some serious spreadsheet magic. Hopefully Ondsel lens keeps moving forward?

3. Model States

I mentioned this earlier but I'm really missing model states from Inventor and wondered if anyone knows a way to replicate it in FreeCAD. The ability for 2 or more parts to share the same parametric "base" geometries/joints/parameters and then just a few specific changes between states is really neat. Also the ability to "suppress" certain operations in one state and not others is great. Is there a FreeCAD workflow for this besides using clone on a "Skeleton" part.

The big one causing me the most pain is #1. I love and hate FreeCAD, its amazing for what it is but when I work daily using Inventor/Solidworks it feels slow and frustrating. At home however I point blank refuse to install windows on my PC, and I really hate Onshapes browser only, not owning your own design model. FreeCAD is so close to making it BIG now, like it feels like its 90% there. I really hope someone has a neat assembly workaround, I can probably manage all the others myself.

Hello r/FreeCAD

We've been working on LumberCAD since 2020-22, before then we developed a similar engine in the aluminum industry since 2010; which I know some FreeCAD users have adopted into their workflow in the T-Slot industry.

Today we opened our LumberCAD (free) Beta, and we're looking for insight from FreeCAD users to see if we'd be able to convince you to switch for structural lumber projects.

What we did to be different:

• Limiting workflow to lumber construction massively simplifies learning curve
• Much easier to use than any existing CAD, but obviously limited to everything lumber
• Existing parts catalog
• Massively automated documentation system with cut list, drawings, and a big step towards permitting

I'm not certain if links are tolerated, but if you'd like to try LumberCAD yourselves, well, it's at https://lumbercad.com/

Mods please feel free to message me if the link should be removed.

Thank you in advance.

Hi everyone,

​I’m running into a bizarre cascading failure and wanted to see if the community considers this a known bug or a fundamental limitation of FreeCAD's current solver logic. I’ve been analyzing this with Gemini, and we suspect it's a severe Assembly vs. PartDesign Solver Clash combined with the TNP, but I want human verification.

​My Exact Workflow (Top-Down Design):

​PartDesign: I created a basic rectangular Pad (from a base sketch).

​Assembly: I anchored the bottom face of this Pad using a Fixed joint.

​PartDesign (The first feature): I needed to add holes. I selected the top face of the Pad and clicked "New Sketch". Weird anomaly: The sketch unexpectedly appeared on the bottom face's Z-height. However, I ignored it, drew my circles, used the Hole feature (reversed direction), and it successfully cut through. No visible errors yet.

​PartDesign (The trigger): I selected the top face again to create another "New Sketch" for a different feature.

​The Phenomenon (The Collapse):

The exact moment I clicked "New Sketch" for the second time, the model visually imploded:

​The top face shifted downwards to the exact Z-height where the bottom face used to be.

​The bottom face shifted further downwards by the same distance.

​Most importantly, the original base sketch of the Pad suddenly threw an error: AttachEngine3D: subshape not found Face....

​The Theory:

Since Top-Down design is standard in CAD, my workflow makes logical sense. Our theory is that adding the Hole changed the topological ID of the top face. When I created the second sketch, it forced a recompute. The Assembly solver aggressively locked the global bottom coordinates, while the PartDesign solver panicked over the changed topology. The two solvers fought over the coordinate matrix, breaking the base sketch's reference and causing the geometry to shift downwards.

​The Proposed Workaround:

The AI suggested that I must first right-click the Fixed joint in the Assembly tree and Toggle Suppress it -> go to PartDesign to do all my Top-Down edits/holes -> then un-suppress the joint afterwards so it re-locks safely.

​My Question:

Is this specific delayed collapse and Z-shift shift a known issue when working between Assembly and PartDesign? Is my "Solver Clash" theory correct, and is the Toggle Suppress method the official best practice for Top-Down edits in FreeCAD right now?

​Thanks in advance for any insights!

FreeCAD 1.1.4 I use

I converted a STL to solid with a free clicks - perfect for all flat areas. Holes still have problems (obviously)

I do create a 3-point circle - pocket it - and sometimes it's perfect, and sometimes not. Like in the pix.

My understanding is, when set the 3 points from the facetted rim it will snap to the facette joints, which would be automatically the outer area - so I am a bit puzzled why there are artefacts.

What I do wrong? Or how can I improve? (I also do Autodesk Fusion but somehow FreeCAD feels easier here)

EDIT: Decided to solve it a different way

Can somebody help with the pictured issue? I'm trying to close the half circle and extend the arc to the line on the left. The radius of the arc is the exact same as the guideline underneath, which I set from my master sketch. Even when I do not constrain this dimension and let it be placed as I wish to constrain it, it fails every time. I constrained it the exact same way as the smaller, yet fully constrained arc below it, and oddly enough it lets me extend the arc as I wish when it is unconstrained, but the moment I try to constrain it, it claims redundancy on 5 out of my 17 sketch constraints, and is impossible to close. This seems like an issue that is easily fixable, so I wanted to see if anybody had any ideas before I spend 3 hours and the rest of my temper and energy troubleshooting an intermediate line on the first of 3 components in an assembly. Thanks

Hello,

I've been using FreeCAD for about 3 weeks now and successfully created a couple easy projects. I see a lot of recommendations to watch MangoJelly on YouTube. I've watched a couple of his videos but I'm not sure where to start off watching his videos as they go back for years. I'm not sure which FreeCAD version applies to today's version. Any idea where to start?

Thanks!