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Comment by resource_waste | Hacker News Reader

I never had any issues with chamfer, wall thickness, or draft angle.

But I won't be like those linux users that pretend 'the problem doesnt exist'.

I just personally havent run into the issue. Curious, what is your experience level? I'm wondering if you are building a house of cards with CAD and not realizing it. Even solidworks will break if you do things in the wrong order.

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Relative newbie. For reference, I started on openscad, pretty quickly realized that was insufficient, started learning FreeCAD before eventually arriving on fusion360. I found Fusion360 much easier to use than FreeCAD

The use case was designing injection molds for electronics enclosures. Something I would say requires subtle and precise nuances at low tolerances but not remotely a jet engine level of complex design at all.

I don’t doubt I was probably doing things “the wrong way” in FreeCAD. But it was very difficult to figure out the right way in FreeCAD oftentimes.

The Part Design wall thickness tool works but is not good.

But in 0.22-dev there is a good sketch offset/sketch frame tool that would let you make an outline wall in 2D that you can then pocket.

Another approach is to make a SubshapeBinder of a face, offset that and pocket it directly.

Fillets and chamfers work but they have OCC bugs and limitations; there are ways to work around them but whereas in Fusion360 you might place geometry on a chamfer, with anything built around OCC it is better to treat chamfers and fillets as “dress-up” only, and do them last. Anything structural is definitely better done in a sketch or with a subtractive sweep on an edge.

Bosses: you can taper pads/extrudes easily enough, and there are some tricks involving copying external geometry of sketches and face/shape binders that can help you match them up across bodies.

None of this is to suggest that FreeCAD is easier than Fusion360. It’s not, and it’s definitely something of a lifestyle choice. (You won’t hear me telling you that you should use GIMP over Photoshop, though).

But it also doesn’t have Fusion360’s limitations: ten or five projects or whatever at a time, reapplying for the license every year, STEP support that could get taken away from you again when Autodesk decides to reassess the free tier, etc.; and I can share FreeCAD as easily as I can share my designs.

Don’t get me wrong, I don’t think Fusion360 is bad or Autodesk is a particularly unusually bad actor. I just don’t want to be dependent on the whims of closed source free tiers in cloud software until I absolutely have to be.

So far, my limitations in CAD have nothing to do with FreeCAD, and my 3D printer isn’t the slowest part of the puzzle. In both cases the issue is me.

The problem of the “right way” is definitely FreeCAD’s primary issue; it’s not as easy to mix the guided flow of Part Design with the more generalised tools in the other workbenches as it should be. (Sketches on curved surfaces are a classic example of this.)

But there is an increasingly broad range of tutorial materials out there now, and the major changes around Ondsel and FreeCAD 1.0 will only improve things.

Totally get not wanting to depend on a closed source cloud provider. Glad to see FreeCAD is becoming easier to use but you did point out its most fatal flaw imo: the kernel that drives the geometry is just kinda broken right now and is buggy and crashes a lot. Good discussion here: https://news.ycombinator.com/item?id=24514191

It will always be somewhat broken; bRep has its limits, and OCC certainly does. But it’s enormously capable and open source, and all we have.

The crashes, by and large, are freecad/qt rather than OCC.

FreeCAD 0.20.2 almost never crashes; I had maybe three in eight weeks of daily struggles with a complex design problem.

Totally get that - one does not simply just wake up one day and casually write a robust, feature complete geometry kernel by themselves, as alluded to in the above linked thread. It is a massive undertaking that requires a team of very smart people and probably years of work. I do wish there was some consortium pushing for a next-gen replacement of OCC though, I would absolutely donate towards that cause. I can't claim to know whether OCC is salvageable to the point that it is possible for it to become as good as some of the closed source ones, but other, more well versed people in the space seem to indicate that it has some pretty fundamental problems with it that are not easily addressed.

There is a Chinese fork of OCC -- I'm away from the computer where it is bookmarked but I think it's called OpenGeometry? No idea if they are really making headway.

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