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Comment by jackyinger | Hacker News Reader

My complaint is that it is extremely modal and as a result not very friendly, not intuitive even to a relatively experienced CAD user.

I’ve used a variety of CAD and it just really didn’t click. I know it’s open source, so not going to be as UX oriented, but still.

I would love to be proved wrong. If there’s something I’m missing please share.

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I've experienced that user unfriendliness too. I'm not at all an expert in this, I'm a FreeCAD newbie that has been trying to decide whether to invest in learning FreeCAD or not.

I keep wishing that FreeCAD had the UI polish of Blender, and ask myself if Blender can do enough of the CAD workflows that it makes sense to learn Blender instead of FreeCAD.

I keep reading that technically speaking, mesh-based modelers are woefully insufficient for CAD tasks. But then I see videos like this, which suggest that Blender can handle most modeling tasks, with the main exception of bevels and chamfers: https://www.youtube.com/watch?v=n5SehCbhxFs

Mesh modeling in blender has similar downfalls to OpenSCAD. When you’re designing a bit of precision equipment (or what have you) you don’t want your circles turned into high degree polygons.

Can a lathe turn a polygon? Can a drill drill a polygonal hole? Maybe you can machine a polygon on a fancy CNC lathe, but you certainly wouldn’t do so for a turbine shaft.

Also for less precise things, say construction, you care about dimensions. Select an arc to get it’s radius for instance.

This is why design for traditional construction techniques best done in boundary representations: https://en.m.wikipedia.org/wiki/Boundary_representation

I will concede that one can easily create nasty insoluble problems with boundary representations if not familiar with the limitations of splines, but this only really is a problem with curvy things like ship’s hulls and aircraft.

There is no downside in my opinion to learning a bit of OpenSCAD, FreeCAD, and Blender and reaching for the right tool when you need it. Personally, I have found the UI/UX of FreeCAD painful to use, but it is sufficient for most of my CAD needs. And after Fusion 360 crippled their hobbyist licensing, I don't really want to get in bed with any of the non-free CAD tools.

I found OpenSCAD to be very friendly for parametric designs, but after a while I switched to the SolidPython wrapper as it was more flexible.

However, I'm hunting for a better way to create 3d models via code (Blender Python?) because 'extrude_along_path'->SolidPython->OpenSCAD->stl export simply could not handle my model.

OpenSCAD is great in some ways, but the fact that everything gets boils straight to triangles drives me nuts. If there were an OpenSCAD equivalent to work with boundary representation models I’d have found my CAD nirvana.

Would this fit the bill?

https://solvespace.com/index.pl

ZenCad?

https://mirmik.github.io/zencad/en/index.html

CadQuery should be better as it is using the OpenCASCADE cad kernel (same as FreeCAD) instead of a simplistic ad-hoc thingy.

Thanks for pointing this out! Looks pretty useful, will give it a shot.

I honestly think CadQuery has more promise as a way to get open source 3D components and modules to the mainstream, because it's fundamentally code, and can be reasoned about as such (diffed, merged, blamed, parameterised, modularised, reused and tested). Putting SolidWorks or FreeCad file into source control is a very different thing.

Also, as it's natively Python, you have all sorts of library support, up to and including things like numpy.

On the other hand, sketching with constraints is very intuitive. Making interesting shapes that aren't trivial CSG demos by fiddling with code just doesn't sound that great.

The future dream mCAD for me is something where extrusions and fillets and other 3d stuff is code, but sketches are GUI edited.

I wouldn't consider OpenSCAD real CAD. It doesn't aid you in design really, it's just a language to represent the design you already have in your head.

Without constraints, you're still doing a lot of stuff directly rather than declaratively, and without a GUI you're mostly limited to geometry you can imagine, because doing anything by trial and error in OpenSCAD takes forever.

The whole thing feels very open loop, like it's meant to be "imagine it>reason about it> code it" rather than "vauge idea > iteration > verify"

I could see it being useful in some cases for high level professional designers though.

The one thing I lack in OpenSCAD is dimensions: there is no good way to add any.

Did you find the Part Design workflow? It took a while for Freecad to click for me but it ends up being fairly similar to other CAD programs in terms of workflow.

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