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londons_explore

When I last used OpenSCAD, I found it rather lacking.

Basic things like 'hollow this object out, leaving a 3mm shell' are nearly impossible.

Anything non-trivial takes minutes or hours to compile, making debugging really hard.

Are these newer tools better?

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I can only speak from a 3d printing perspective, and I've only tried OpenSCAD and FreeCAD.

As rough as OpenSCAD is, I find myself coming back to it, because CAD-as-code is just so useful (including leaving comments). For bashing out quick, fairly simple models I still like it. The various OpenSCAD DSLs can help, but also not when they get superseded or get in your way. I think the review on the posts blog summarizes it well [0].

FreeCAD is apparently capable, but the UI defeats me. IMO, it tries to do too many things and doing none well.

The post doesn't really do a good job of comparing how mature the others are, so I'm not sure. But if CadQuery works as well as OpenSCAD or better, I may just be sold.

[0] https://learn.cadhub.xyz/blog/openscad-review/

AFAIK FreeCAD has Python API.

Though dunno about UX using it, probably not as streamlined as OpenSCAD, though maybe more powerful?

https://wiki.freecadweb.org/FreeCAD_API

I kinda think the many of workbenches in FreeCAD might have been a mistake, it's confusing to know where to start.

I'm inclined to agree, although I'm not trying to bash FreeCAD. The benefit of hindsight is unfair, and FreeCAD set out to be a "full" CAD package, which are naturally complex. Widespread 3d printing came after FreeCAD's inception. No doubt the 3d printing "sphere" could benefit from an open Fusion 360 replacement though...

Yeah, I've tried to digest the Freecad UI / worflow many times, it's just horrible.

There's definitely room for a UI remix that just embeds a couple of critical workbenches for specific workflows. I use it for designing things for 3d printing, and I spend all of my time in 3 workbenches, maybe 4 if I'm doing something unusual. There's a lot of UI/UX noise I don't need to care about.

There is, it's called SALOME. I've found it to be more intuitive than FreeCAD and they share a lot of code. Blows my mind that it's not more widely known. Bad marketing I guess - it's billed as a CFD preprocessor.

https://www.salome-platform.org/

I'm curious: have you found a way to export your models to a mesh file format (eg obj) with some amount of control tessellation?

Last I tried, I didn't manage to find the control. I assume it exists, but the UI was simply to painful to navigate.

I mention SALOME above - it's a bit of a sister project to FreeCAD, and it has extensive mesh generation facilities as part of its role as a CFD pre-processor. I've no doubt you could use this to assert fine control over a surface mesh export.

> I've only tried OpenSCAD and FreeCAD.

This is the crux of why you've come to this conclusion: FreeCAD is frustrating to work with compared to other CAD platforms.

OpenSCAD, as noted by the author of the website sorely lacks a number fundamental features.

    - proper fillets

    - proper chamfers

    - surface-surface intersection

It is also limiting because it can only generate triangle meshes and can indeed be slow when models get big

However, for many situations, especially for prototyping, it is good enough and a really great tool.

It is definitely the first tool I turn to when I want to model a simple part quickly.

> Basic things like 'hollow this object out, leaving a 3mm shell' are nearly impossible.

Yeah, I think that's a consequence of how they're constructing the objects. But things like signed distance fields make that easier* because it'd just be "expand the SDF by 3mm" - https://github.com/fogleman/sdf has `shell` for this.

* if you can wrap your head around the math/geometry, I guess

Except that only works when the distance field accurately represents Euclidian distance, which it certainly won't the minute you apply any sort of non-trivial distortion.

Do you have examples?

Sure. Non-uniform scaling, bends, and twists all render the distance field non-Euclidian.

I agree. Articles like this may be confusing to people new to or unfamiliar with CAD: Tools like OpenSCAD aren't on the same level as the better GUI tools like SolidWorks and Fusion. Even FreeCad is a better bet for anything other than experimenting.

You can probably try ImplicitCAD . I have not used yet, but it's on my stack of things to try for the next time OpenSCAD fails me. And it does have a shell operation.

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