alt Hacker NewsOpenSCAD is kinda neat
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It is kinda neat, but OpenSCAD's limitations are the main thing that motivated me to write this Python library to generate 3D meshes used signed distance functions:
https://github.com/fogleman/sdf
One big plus to doing it this way is that it's "just" Python and you can use arbitrary logic to help construct your model.
You can even load an existing 3D mesh and operate on it as an SDF. Great for hollowing, chopping, eroding/dilating, etc. existing models.
I should probably do more with this project. I think there's a lot of interest in this space.
Just started using OpenSCAD recently and love it. While most CAD tools have a million features to learn, OpenSCAD is completely described by a cheat sheet you could print on a piece of A4 (like most programming languages).
I would really recommend using the git master than the latest release though. The last release was 2021 but they are still actively working on it and it's much faster now.
I also have to recommend the BOSL2 library which means you don't have to implement all of those one million features from typical CAD software yourself. Its definitely got a bit of a learning curve but the fact that you can always default back to vanilla OpenSCAD and that you can actually see how stuff is implemented makes it much more satisfying to me to learn than learning what all the traditional CAD GUI buttons do.
Maybe it's improved since I last used it (seems to still be an issue per a 1 minute google search), but OpenSCAD doesn't really have easy support for dimensioned drawings.
While it was very handy for my programmer brain to create a few 3D printed things, when I wanted to create a drawing for something I'd make myself, adding dimensions seemed very unwieldly. I used a different CAD program for those projects (maybe Autodesk Inventor?).
The great thing about OpenSCAD is that it makes it easy to 3D model things which may be described using spheres, cylinders, and cubes which are stretch, and/or rotated, and arranged in 3D space.
The awful thing about OpenSCAD is that what one can model in 3D is limited by one's ability to mathematically stretch, rotate, and/or arrange spheres, cylinders, and cubes in 3D.
For folks who want "real" (read mutable in normal terms of scope) variables there is a Python-enabled fork (which should become part of the main release presently:
I really wish OpenSCAD had objects, so you could use something like box1.width rather than having to declare variables for such things.
I tried using Build123d, a Python library that lets you use all of the features of Python. And it's supposed to allow specifically things like box1.width, but it's always 0. Lots of other issues/bugs too, and severely lacking in ddocumentation.Maybe it'll get there some day.
For me as a casual 3d-modeler, my favorite thing about OpenSCAD is that I don't have to learn a new application the size of Photoshop with everything hidden 7 levels deep in some menu that is probably intuitive for some people who learned CAD in the 80s.
Instead it's basically like graphics programming, with a couple of basic primitives, some linear transformations and a bit of set theory. When I do a model a month and get back to previous work, I read a few lines of code and know exactly how I achieved the result.
You don't have to use their editor either, there is a whole list of alternative editor plugins.
OpenSCAD can automatically re-render a preview as soon as the external editor saves to disk
https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Using_an_...
Ah OpenSCAD. I wrote a tutorial a long time ago about the 10 things you need to know to get started.
https://cubehero.com/2013/11/19/know-only-10-things-to-be-da...
It's a lot of work to make models that are useful in real life, but for some things it's worth it because it's sooo nice having 2k of plain text that describes an entire object, and it's even fully parametric, and it even comes with a customizer panel for the parameters, so every model isn't just a model, it's a model generator app, and even has meaningful diffs in git.
The same model in freecad is like 6 megs of zipped xml and realistically not nearly as usefully parametric.
That couple-k of plain text is such a huge deal that it makes all the other difficulty worth it for mechanical/functional stuff.
Tip (a lot of people don't know this): you can set the resolution by setting the $fn variable. This can be useful when you want to export smooth objects.
$fn = $preview ? 32 : 64;An interesting use case of OpenSCAD is open source hardware with many contributors - the reasoning being that we only have mature version control tooling for text-based files (say git), and so your CAD design should be text-based. I was introduced to this idea by https://openflexure.org/projects/microscope/ - they managed to build a fairly complex 3D printed microscope project on this principle.
I'm aware of Onshape having a git-like workflow as well, wonder how the two compare! A fully cloud-based suite would probably not work well for an open source project.
I like openscad it allowed me to create a shed generator which also provides material quantity output, so an accurate shopping list is created - all done in code super impressed. I could not figure out how to do the same thing in standard cad software.
It is amazing. I spend more time in OpenSCAD than in any other program I use and I'm amazingly productive with it. 3 to 4 cycles / day, the longest time is waiting for the printer to cough up the next iteration, then it is building debugging and improving again.
The power of parametric cad is such that I wouldn't be a 10th as productive using an interactive cad system. And because it is effectively software you are writing (even if it compiles into physical objects) you can use all of the goodies that you can use to manage software. Diff files, git, kompare, branching, merging. It is nothing short of amazing, it is like I have a design team and a prototype injection molding facility in one. And the turnaround time is something you'd have killed for in the 90's.
It's super useful, been using with my 3D printer to print things such as an adapter to connect a Canon EF lens to night vision tube and parts to link motorised linear stages together.
Currently I'm playing with a gear library which is part of BOSL2 (https://github.com/BelfrySCAD/BOSL2/wiki/gears.scad), to make something to rotate a polariser in my microscope.
I found that combining OpenSCAD with SVGs for extruding complex shapes is quite powerful. I made a map of Manhattan that could not be handled by any other CAD program I tried without crashing, but OpenSCAD handled it really well.
I wrote more about it here, although I only mentioned OpenSCAD briefly https://hackaday.io/project/202488-manhattan-subway-map/deta...
There's a tutorial? Maybe I should have started there.
I recently started messing around with OpenSCAD too. I found these boxes that are great for storing the tiles for various 18xx railroad boardgames: https://www.printables.com/model/287297-parametric-18xx-tile...
Cool thing is that you can easily print them in whichever size you like, and the sizes in the supplied files are rather large, so I tried some smaller sizes, and discovered some details weren't actually centered properly, so I dove into the code, tweaking some bits here and there until I got it centered properly.
Then my dad asked me to print boxes for a game that had slightly larger tiles, so I needed to tweak the sizes, the thickness, and made everything just a bit more configurable.
I've got another idea I haven't tried yet: print the shape of the track on the tile on the spot its meant for. That's a whole new feature and not merely tweaking an existing one, so maybe it's time to finally learn how this format actually works.
Although I did see in the code that you create shapes through intersections and substractions with other shapes. And that's where I got stuck. Maybe it's time to pick it up again. It's a fun way of building shapes.
I rage-quited every other CAD program. Then I found OpenSCAD. Now I'm looking forward to work in it every time I need to do some 3d modeling (usually new part model for kicad or some other project).
Check out https://zoo.dev/
I went from OpenSCAD -> cadquery/build123d -> Zoo/KCL
It still is early days, and it needs some more helper functions but it's really nice having two-way capabilities (not just code -> model, but also the reverse).
Of course having Text-to-model as a first class citizen is also nice.
I completely agree! https://overdesigned.org/shhh-dont-move-it-cant-see-us-if-we...
I created a simple go library to output OpenSCAD code a few years ago. https://github.com/richi0/gocad
I’ve used OpenSCAD for 3D printing random objects for years. It’s the perfect tool for designing super simple geometric objects, because it giant demands that you remember hardly anything about his the interface works. Contrast with Fusion 360 or any other more powerful tool, which are fantastic if you use them daily but a slog of you only boot them up a few times a year.
Also with OpenSCAD, you can feed the documentation to your favorite LLM and ask it for a starter design of whatever you are building. (Or you can skip the documentation; it is in the trading data after all.) Maybe in the future that SVG Pelican on a bike test will be a 3D model in OpenSCAD.
Also check out CADQuery and or build123d (python equivalents)
That let() {} expression seems pretty similar to the LISP let()() form: https://lisp-lang.org/learn/variables
If you are a programmer OpenSCAD is likely for you. It certainly has benefits in things that are repeating patterns (gears and such)...and if your mind is good at visualizing things in "code" things will likely go a lot faster.
I personally do better with CAD software such as fusion or freecad since my mind doesn't work in the code realm since I have more of a hardware mindset. Translating the picture in my head to code is more difficult than drawing it using the standard CAD set of tools.
My opinion on OpenSCAD is that it is a very useful piece of software which many have used to make some very interesting things. If you have a background in code I recommend giving it a go. I largely view it as "the coder's CAD".
I've been experimenting with using Claude Code and the Gemini CLI to generate OpenSCAD with the renderer in the loop.
https://github.com/rahulgarg123/openscad-mcp
It’s still strictly worse than what these models are capable of for general-purpose coding, but for simple tasks where precision isn't the bottleneck, it's surprisingly decent.The "aha" moment for me was an image-to-object workflow: found a geometric design on the web --> generated OpenSCAD to match the image --> 3D printed it. Going from seeing a JPEG to holding the physical object in a few hours.
Oh I had no idea that OpenSCAD was a programmatic toolkit. I recently bought a 3D printer and I don't model so much as describe to Claude Code how to write a Python script that will generate the required STL that I then rescale or whatever in Bambu Studio. LLMs are great at code-oriented stuff so I've stayed away from traditional modeling tools because I assumed you'd have to point and click and so on and I don't really want to learn the ins and outs of their interface. I just need the right mesh made.
The chatbots kept recommending I try using OpenSCAD but I resisted without even giving it a look. The results I had with just the Python script are quite adequate for the tasks I had. You can just ask the LLM to add a fillet to a vertical pin on a plane or to chamfer some edge and it is pretty good at doing it.
https://wiki.roshangeorge.dev/w/Blog/2025-12-01/Grounding_Yo... if you want to roughly see the workflow.
I'm going to try using OpenSCAD for things in the future. Does anyone else use exclusively an LLM with OpenSCAD (I used Claude Code and Codex) and if you do what did you do to make it more effective? The Python script wouldn't always generate printable meshes so I had to give it a check script to operate on.
I find myself using OpenSCAD regularly to 3D print little things for the house. (Most recently: hooks to attach Christmas lights to our roof deck's glass walls)
And when something gets too trick, ChatGPT is amazing at writing in it. Often it nails the whole design in the first try, like https://bsky.app/profile/bradfitz.com/post/3maelwomyw22n to mask off certain Raspberry Pi pins to make reassembly of projects easier later.
A long time ago I read that CadQuery has a fundamentally more powerful geometry kernel than OpenSCAD, so I dropped any attempt to try OpenSCAD.
Years later, I never actually got the hang of CadQuery, and I'm wondering if it was a mistake to write off OpenSCAD.
I am pretty new to CAD, so I don't actually know when I would run into OpenSCAD's limitations.
It’s pretty neat but for my taste the language is too functional. I don’t think a purely functional paradigm works well with CAD parts and the way they are constructed. The language gets in the way. Debugging complex parts is also quite difficult from my experience. But with some better tooling I think it could be absolutely great.
worth also looking at cadquery, build123d and similar
OpenSCAD has become my go to with my 3-D printer for dumb little things. And the best part is LLMs are getting decent / pretty good with it!
My favorite thing I’ve printed is a little downsize coupler for the cool shirt system I built for my spec miata. It’s realllly silly & small thing, but it saved me!
openscad is quite nifty for small geometric projects. unfortunately it lacks some Features that make most bigger cad programs really useful... for example: - the ability to select faces/paths from a render, which can be hugely helpful when modifying complex models. - the ability to do constrained sketching in both 2d and 3d - caching at intermediate render levels - nested Projects and joining parts with mechanical constraints. it's still pretty nifty but very niche. I personally would dream of having the tools of a tool like fusion 360 or Catia, but in a gilly textual progemmatic way, while keeping the ability to select objects from the rendrr view.
I haven't tried the latest models but for at least a year LLMs have been mostly able to generate openscad to match my descriptions.
It's neat that I can tell the computer what I want in words and then have that object come out of the 3D printer
OpenSCAD is great! I used it to create a bunch of things to cut on a CNC router over the years. Best achievements were a scale model of Mount Rainier and some one-piece picture frames with text cut into them.
Mind you, it can't export to step file. That makes it impossible to re-use the models in other CADs to make assimblies. Also it's tedious to use for 3d printing when you want to include modifier objects with your model. Otherwise it's great and good enough for part modeling
I have solved the only problem OpenSCAD ever had and that is
total lack of interactivity.
Anything that helps people shun Autodesk's despicable, anti-customer and anti-industry practices is laudable.
The OpenSCAD kernel is significantly overrated in my opinion. Many operations take ages to compute or are not possible at all
Ok if you want to generate a couple of cubes, but if you want anything advanced the kernel quickly falls apart
FYI I’ve had really surprising success using AI to generate openscad code.
And even if it’s not perfect it saves a lot of time looking up the documentation and generally gets the relationships between objects right.
OpenSCAD is great if you follow a subtractive workflow. Define simple stock geometry, and subtract away each feature with slightly wider primitives to avoid zero thickness intersections. This ensures you will not get weird bugs later, and a fairly accurate part for plastic printers.
As many correctly pointed out, STL & DXF are not considered professional file-formats anymore by some people. Some fabricators will not respond to quote requests, as without a Step file they are literately self-confessed useless clowns without Onshape/Fusion true solids handling the ugly math.
It is partially a unofficial standards issue, but customers without Step files may have to look around for fabricators. YMMV =3
Once had a complex model that would fully crash and lockup fusion, but once redone in openscad rendered after a little while. (badly designed + slow pc at tye time)
I’ve been using it for almost a decade and I still miss proper fillets and chamfers (and yes, I know the usual tricks).
I love the model, it's nice to be able to generate things parametrically instead of grabbing knots with the mouse. so I use scad pretty often.
but it has real problems - the language is weird and unfortunate. not anything super fatal, just the obvious product of evolution that would be more cohesive if it were architected wholesale
epsilons are really unfortunate. you have to expect that after getting what you want in the whole, you're going to have to scan over the whole thing and look for cracks or collision where there shouldn't be
performance is quite sad. here you are happy going back and forth between the view and text windows, but as you go on, it starts taking .. minutes.. to update the view once you have a reasonably complicated geometry
high-level operators would also be nice. I made the mistake of using a thread library once, not only did that make my model unrenderable, there was so much noise in the model and the manufacturing process I had to make 3 expensive test prints in sintered nylon to get the fit right. (I'm thinking an annotation on a cylinder that says 'standard 1mm thread')How does this compare to something like Zoo?
Neat-ish.
I don't really see why that code is better, more logical, more readable or more robust than the equivalent quite trivial parametrics in more or less any GUI CAD program, and I think the geek discourse is really harmed by people who don't understand the value of the things that OpenSCAD can't ever offer.
OpenSCAD is very cool, but completely unusable once you understand how great state of the art CAD Software like Fusion or Onshape is.
The big distinction is that those work implicitly, while OpenSCAD requires you to be implicit.
OpenSCAD is great, and I use it all the time.Especially these days if you combine it with an LLM agent like codex and start vibe coding objects (see my other post on this).
However, there are a number of limitations that are truly and deeply frustrating.
1. The language is downright weird. Don't get me wrong, it's a very nice little exercise in implementing a functional-tasting scripting language. Someone obviously wanted to scratch a functional DSL design itch and he did, but the result is unfortunately extremely limiting. Creating a function that does not return geometry is barely possible (only bloody lambdas IIRC). He should have picked python instead (and yes, I know about SolidPython2)
2. From my POV: the main headache with OpenSCAD is there is no way to partially evaluate an object and use the result of that partial evaluation in the rest of the construction. For example, if you try to take two complex assemblies and place them tangent to one another ... very good luck to you sir, I pray and hope the 3D math is really strong with you.
Whereas: if you had a simple rayIntersect(csg_tree, line_in_3d_spce) that would return the first intersection and two normals ... something you can reuse in subsequent transforms and construction, man would life be simpler.
These days, with LLMs you can sort of build a scaffolding to work around this by asking the agent to break down the assembly in multiple stages and use external libraries to do the partial eval for you, but ... ugh ... what a mess.
3. Speed. The moment your CSG assembly gets complex (e.g. uses a ton of morpho ... hull, minkowski, etc...), OpenSCAD crawls to a halt.
4. NO FILLETS. The age-old, standard methodology of building things CSG style with cubes, spheres, cylinders, etc ... and then once the object is finished adding the rounding ... simply not possible with OpenSCAD. Adding fillets after the fact once you've built a complex CSG tree ... nightmare with OpenSCAD.
So, YMMV, but caveat emptor, if you get serious with the toole, you're bound to hit some very hard walls.
OpenSCAD is perfect for the "programmer's brain" approach to CAD. Being able to parametrize everything means I can design something like a project enclosure once, then generate variants for different screen sizes or component layouts by just changing a few variables.
Pro tip: Use the latest nightly build and switch to the Manifold backend in preferences. Render times drop from minutes to seconds for complex models. The official 2021 release is painfully outdated.
Also, the BOSL2 library is essential - it adds proper filleting, rounding, and attachment operations that vanilla OpenSCAD lacks. Makes the difference between toy projects and actually useful designs.
The Git-friendliness is underrated too. Diffing .scad files is trivial compared to trying to understand what changed in a binary Fusion 360 file.