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')
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.
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.
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.
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!
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.
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.
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 think people should also give Bowler Studio a shot. It has a pretty decent Java-based CAD thing, and it even has built in Clojure support, with physics simulation support and everything. I really like it.
> 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.
Not at all. You can build any polyhedron you want using the polyhedron command.
Which would be an enormous pain to write out by hand every time, but I wrote a function once upon a time to generate a polyhedron from a stack of layers, each of which is a list of points, and haven't had to mess with old cubes and spheres since.
One annoying thing is that the default way of writing programs in OpenSCAD uses 'modules', which are a bit limited compared to functions (you can't store them as values to to functions or other modules). I worked around that by writing a module that interprets arrays (think S-expressions) that representing the shape, and then just build up that S-expression-like thing with functions and whatever.
Once you've built your own programming language inside OpenSCAD it's perfectly usable. :-)
This might sound like sarcasm but I actually do prefer this to dealing with Python's mutable state jungle / package management nightmare.
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".
There is no explicit iteration, so if you want to do flexible spacing for any reason, like distribute a feature evenly along a dynamic length, you need to use recursion.
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.
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.
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.
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
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:
SDFs are very neat up until the point where you need to build parts that have very precise specifications.
Something like two precisely interlocking gears with a tooth geometry with a profile that's the developed curve of the opposite tooth is a nightmare to build with SDFs
Or precise fillets.
Or hard intersections and differences.
Very useful for doing soft, squishy shapes, less so for hard CAD.
Also, a suggestion: in your project, please consider using Wavefront OBJ as an output format, it is a much, much better choice than STL (STL can't represent the actual topology of the object, it has to be reconstructed).
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[ 4.1 ms ] story [ 84.0 ms ] threadbut 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
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.
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.
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!
https://github.com/gumyr/build123d
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.
The big distinction is that those work implicitly, while OpenSCAD requires you to be implicit.
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.
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
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:
https://pythonscad.org/
Thanks for this, didn't know about it.
How does that compare to solid python 2?
https://github.com/jeff-dh/SolidPython
Not at all. You can build any polyhedron you want using the polyhedron command.
Which would be an enormous pain to write out by hand every time, but I wrote a function once upon a time to generate a polyhedron from a stack of layers, each of which is a list of points, and haven't had to mess with old cubes and spheres since.
One annoying thing is that the default way of writing programs in OpenSCAD uses 'modules', which are a bit limited compared to functions (you can't store them as values to to functions or other modules). I worked around that by writing a module that interprets arrays (think S-expressions) that representing the shape, and then just build up that S-expression-like thing with functions and whatever.
Once you've built your own programming language inside OpenSCAD it's perfectly usable. :-)
This might sound like sarcasm but I actually do prefer this to dealing with Python's mutable state jungle / package management nightmare.
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".
There is no explicit iteration, so if you want to do flexible spacing for any reason, like distribute a feature evenly along a dynamic length, you need to use recursion.
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.
Ok if you want to generate a couple of cubes, but if you want anything advanced the kernel quickly falls apart
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.
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.
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.
Something like two precisely interlocking gears with a tooth geometry with a profile that's the developed curve of the opposite tooth is a nightmare to build with SDFs
Or precise fillets.
Or hard intersections and differences.
Very useful for doing soft, squishy shapes, less so for hard CAD.
Also, a suggestion: in your project, please consider using Wavefront OBJ as an output format, it is a much, much better choice than STL (STL can't represent the actual topology of the object, it has to be reconstructed).
https://pythonscad.org/examples.php
(search for "sdf" about halfway down the page)