Discussion
CadQuery
ozmaverick72: Interesting. I have played with OpenScad a bit. This looks similar - i guess the difference is the syntax is python - any other major differences
DrNefario: CadQuery can export STEP files, and is overall much nicer to use in my opinion.
xrd: I've been using Gemini to generate openscad programs for use with my 3d printer. Is cadquery a better option I wonder?Why do you say it is better than openscad?
colechristensen: Neat!I'm working on a CAD kernel in Rust with a frontend either as a Blender plugin or a Blender fork (leaning towards fork at this point) It's not at all ready but I have reached first part status (before going back and rewriting a large chunk of the kernel)
xrd: After reading some of the docs it does look fun.Python, so leverage your Python skills and existing libraries.A nice GUI so you can build, view, tweak, review, iterate.Will be a nice new toy...
hgoel: CadQuery and build123d have been very handy for prototyping stuff for 3d printing. AI still isn't quite good enough to generate correct scripts, but AI autocomplete at least helps with putting together small snippets.My last project involved modeling a cosplay helmet shell in blender, it was a low poly design, so I exported it to an OBJ, then put together some Python to load the OBJ, give the triangles some configurable thickness etc. Then I used it to explore how to print the helmet in such a way that the outer surface would be too clean to tell it's FDM printed, without needing to do any sanding.Initially I explored having cadquery put a number on the back of each triangle and I'd assemble it like a puzzle, but that didn't work out. Eventually I figured out how to cut it up into parts that would also eliminate the need for painting and outer surfaces would be clean, and because it was in code, changing which part a triangle belonged to was a matter of moving the corresponding index into another list.I probably could've managed it all in blender too, but being much more comfortable with code, it was easier for me to play with normals and manually turning each piece into a solid.
gcr: OpenSCAD is all triangles and vertices. Fillets are difficult to do. Outputting circles/spheres generally requires you to for-loop over vertices a lot.Libraries like build123d and cadquery use OpenCASCADE, a boundary representation kernel. You think in terms of the enclosed solid and perform operations - boolean add/subtract, fillet/chamfer, stamp text, etc - that return a new solid.
gcr: Here's an example!I recently used their sister library (build123d, same devs) to build a rotary slide rule bracelet for multiplying three-digit numbers. It was a great experience and wouldn't generally be easy to do with Fusion 360. My bracelet gets quite a lot of comments when I wear it in public. :-)Here's an IPython notebook with lots of pictures so you can see how the different operations come together: https://github.com/gcr/sliderule-bracelet/blob/main/version-...build123d is quite different stylistically from cadquery, but this should give you the flavor of programming-oriented CAD at least.
aaronbrethorst: how does it work? (the multiplication)
double0jimb0: It’s a neat part and design, but you are overselling how hard that is to make in CAD. Flow would be revolve the organicy cross section, then create offset surfaces from the torus you had created, the notches are from creating new bodies and then body subtract + circular pattern, etc. Not necessarily a quick job, but seems pretty straightforward.
7bees: I'm not sure I understand your comment; OpenSCAD has functions like sphere(), cylinder(), etc. Most OpenSCAD models I have seen are built up primarily from solid primitives combined using boolean operations, just as you describe for the other tools.https://en.wikibooks.org/w/index.php?title=OpenSCAD_User_Man...
lutusp: I create CAD instructional videos based on SolveSpace, and I sometimes try to get people interested in CADQuery as well, but many people interested in CAD will learn SolveSpace or another similar design program, but don't have the programming background for CADQuery. Too bad -- in many ways, for many projects, CADQuery gives better results, especially if a single design needs to be recreated in a range of sizes.
Loic: Becaus ln(A*B) = ln(A)+ln(B), you need 2 sliding elements and you work in logarithmic scale. Look at "slide rule"[0], this is really nice stuff.[0]: https://en.wikipedia.org/wiki/Slide_rule
girishso: Came across a similar tool replicad. https://replicad.xyz/Anyone has used it?
seltzered_: Theres a better description of the differences here: https://build123d.readthedocs.io/en/latest/OpenSCAD.html#tra...Some of the differences may be in when you are trying to reference a face/edge to build off of, not just about the primitive function being used.
ginko: Guess this is a good opportunity to plug the DIY trackball I made using build123d:https://github.com/ginkgo/trackball/
RobotToaster: Openscad can export to CSG, which can be imported by free cad or converted to STEP https://github.com/gega/csg2stp
ponyous: Another library I have to integrate and benchmark against OpenSCAD for my AI SaaS[0]. I am really curious how constructive solid geometry compares to sketching and extruding that CadQuery is build on.Anyone curious in the writeup? I have a pretty good harness for evaluating 3d generation performance.[0]: https://grandpacad.com
jetter: If you like this, you should definitely check modelrift.com which allows to build awesome cad models thanks to OpenSCAD and smart AI assistant.Community built examples: https://modelrift.com/models
Doxin: OpenSCAD works natively with triangle meshes. sphere() will create a spherical triangle mesh.These libraries on the other hand can natively represent a sphere for instance. This means that during CAD-ing you don't need to worry about resolution, that's a consideration for export only.
flowerbreeze: Do you mean that OpenScad performs boolean/other operations on triangle meshes, but these libraries don't until output? So they might instead use curved surfaces/edges etc as outputs for operations and only convert to triangles for output or export at the very end?
maouida: CadQuery was an inspiration when I built FluidCAD. I wanted the workflow to be as close to traditional CAD as possible with more interactive UI.https://fluidcad.io
Doxin: yes, exactly.
atoav: [delayed]
fxff: At the time of writing this there are 24 comments, of which 4 promote alternatives. I feel that recently the number of shameless plugs and check-out-my-SaaS's surged drasticallyhttps://news.ycombinator.com/item?id=47803846 https://news.ycombinator.com/item?id=47803475 https://news.ycombinator.com/item?id=47802988 https://news.ycombinator.com/item?id=47803416
adrian_b: I believe that in general the comments pointing to alternatives and the shameless plugs are useful in these HN threads.Such comments have become more useful recently, when Internet searching has started to provide an avalanche of garbage links, to Web pages that only summarize or repeat the primary sources, frequently with errors and failing to point to the original sources.Even if inspecting the suggested alternatives may show them as worthless, finding this may still save time over using a search engine and having to filter an order of magnitude more misleading links.
pyb: Is this the OpenClaw effect?
somat: While true your argument is weak, for example in pov-ray the shapes are pure exact mathematical concepts. But nobody is saying how great this is for 3d printing or general cad work because it's not. The real key benefit from these programs is the interchange format they can generate, something you can feed to a machine, this prevents it from ending up like pov-ray, a terminal process only fit for generating pictures. Fillets are difficult to do in openscsd because fillets are difficult to do in general. What your argument probably should have been is that if openscad had chosen a geometry kernel where fillets were already solved it could then do fillets. Which is the sort of obvious tautology that helps no one.Now I am off to see if anyone has ever built an export plugin for pov-sdl, either a 3d rasterizer(g-code slicer) for 3d printing, or a boundary layer mesh generator for import into another program. language wise it is probably equivalent to or better than the openscad sdl,One subtle advantage to using python as the sdl is that it gets access to the vast corpus of python modules out there. Most of which are probably useless. but one thing I want to try is to see if I can use sympy to define a more declarative style of constraint.
ncrmro: How does this compare to anchorcad?
WillAdams: It was a lot more interesting to me back when it first launched and it was a FreeCAD workbench.Previous discussions:https://news.ycombinator.com/item?id=24520014 (6 years, 49 comments)https://news.ycombinator.com/item?id=30232344 (4 years, 43 comments)https://news.ycombinator.com/item?id=30219940 (on Hackaday, 4 years, 28 comments)https://news.ycombinator.com/item?id=17038257 (8 years, 16 comments)https://news.ycombinator.com/item?id=28083578 (a Show HN from 5 years ago w/ 1 comment)There are a lot of tools in this space, esp. these days when "Vibe Coding" allows folks to knock one out w/ a prompt. Most folks jus use OpenSCAD which with its large user base and weaknesses which are (mostly) not exposed by 3D printing is great, so long as what one wants to model is easily described using mathematics/programming techniques which are familiar to the user.I'd really like to see an interactive opensource project follow OnShape's lead where a scripting language (for OS, FeatureScript) is used as a wrapper around the geometry kernel, then the graphical UI creates the model using that language, and one can always inspect the resultant code. It seems to me that this <i>should</i> be workable given the observation:https://news.ycombinator.com/item?id=31471109>Parametric CAD, in my view, is a perfect example of "visual programming", <BR> >you have variables, iteration/patterning reducing repetition, composability <BR> >of objects/sketches again reducing repetition, modularity of design though a<BR> >hierarchy of assemblies. The alignment between programming principles and <BR> >CAD modelling principles, while not immediately obvious, are very much <BR> >there. An elegantly designed CAD model is just as beautiful (in its construction) <BR> >as elegantly written code.but these days, I'm mostly using Open(Python)SCAD (which is in the process of getting merged in to the main project).
WillAdams: Where are your CAD instructional videos available?I'd be very interested if one of them compares/contrasts SolveSpace and CADQuery.
Karliss: It isn't even necessary to create triangle meshes during export. You can export as step files. It is a commonly used brep based file format supported by almost any "proper" CAD software. Triangle mesh based modelers can't easily export good step files because they don't operate at that level of abstraction.
WillAdams: Whether or no that will be useful/editable will be determined by what sort of objects and modeling approaches were used --- it's pretty easy to make a file which results in a nightmarish triangle mesh representation which is a nightmare to edit.
maouida: +1 for what adrian_b answered above. All the promotion are for free open source projects and none of them is profitable. I think this is totally fine, people like to know about alternatives and all these tools are for the purpose of learning and making parametric CAD more approachable to users. They have same goal with different implementation.
lutusp: Are you asking how the bracelet multiplies two numbers? It's the same idea used by slide rules -- you take the logarithm of the two numbers, then add the logarithms instead of multiplying -- same result, with somewhat less accuracy depending on available decimal places.This method was widely used in the pre-computer era to save time in calculations. Tables of logarithms (and slide rules) were a mathematician's best friend.
acidtechno303: lol, as an engineer I'd never considered that other disciplines used slide rules voraciously
Cargo4286: Not perfectly relevant but build123d docs have an example using sympy as part of a solving constraints for a design. https://build123d.readthedocs.io/en/latest/tttt.html#t-24-cu...
junon: This looks amazing. I'm going to give this a try later.If I have a DXF or something of the outline of something (a PCB in this case) can I import it and build around it somehow?
ReptileMan: PSA - Codex is really good at creating step files for simpl-ish objects with it.
fainpul: > wouldn't generally be easy to do with Fusion 360Actually...https://www.youtube.com/watch?v=DNiQJyRTs50You would create the numbers and marks in a vector drawing program (Inkscape, Affinity Studio, Illustrator) and import that into Fusion.
maouida: Only step import at the moment. I'll add svg next.
stanko: As someone who uses JavaScript/TypeScript, I love Replicad. It is super easy to create and share parametric models from their online editor without any accounts.I keep my models on github[0]. Disclaimer, they are pretty niche things I needed around the house.[0] https://github.com/Stanko/3d-cad-models
