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Comment by sokoloff | Hacker News Reader

I used OpenSCAD almost exclusively for 5 years (Mech E by degree, but computer programmer by profession) and switched to Fusion360 in the last 3 months.

For me, within 6 hours Fusion was night and day more productive (even after a lot of experience in OpenSCAD). As one example, it was so much more productive that I can think of only 2 OpenSCAD designs in 5 years where I bothered to add fillets for strength and appearance. It's just too damn much trouble.

In Fusion360, I'll often have a simple part whipped up in 15 minutes and then spend 1 extra minute adding fillets and chamfers as needed. In OpenSCAD, that same part would likely be 30 minutes for the base part and the fillets another 15-30 minutes (with fairly poor performance once added).

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That's fair enough. It's unfortunate that adding fillets is a big design change in OpenSCAD while it's something you can easily add last-thing in other packages.

Because it's so programmable, most things can be made fairly easy if you think of them in time, by writing procedures, once. I'm interested, actually: I would have thought that long-time users would have developed some sort of tip or trick for this, recognising at the start the kinds of changes that might be difficult to make laters and planning them in at the start. Maybe internal rounded corners are just too much hassle any way you look at it.

I never found a good way to semi-automatically do fillets. I did get good at many other kinds of manipulations, using the ! and % operators to help me "see what I'm doing", etc.

If you need boolean ops on cubes, cones, and spheres, OpenSCAD is great. If you need fillets on an oblique cylinder that intersects a curved surface, you're in for a much longer walk.

I have to admit that I’m not-so-secretly hoping someone will post “hey, here’s my secret to easy fillets in OpenSCAD” and I can learn a new trick.

Sorry, no OpenSCAD secrets, but a different tool: Cadquery has fillets in their quickstart tutorial:

https://cadquery.readthedocs.io/en/latest/quickstart.html

...and the fillet command is built-in:

https://cadquery.readthedocs.io/en/latest/classreference.htm...

Wow. That looks great. I'll play around with it and recreate a few of my recent F360 designs as concrete training material.

Thanks!

For fillets / chamfers of simple objects I've been using BOSL2:

https://github.com/revarbat/BOSL2

They come with fillet / chamfer masks, but in general I've been just using their cylinder / cube replacements that generate rounded intenral corners, and just diff'ing them out of existing shapes.

In general, I've gotten a long way by just starting with chamfered/filleted shapes (the library includes a neat way of specifying which edges of the shapes you want filleted), and using the intersection / difference of filleted cubes, cones, and cylinders.

Intersections on curved surfaces seem impossible any way of looking at it (minus some projection nonsense, but that's expensive in openscad)

My experience with Fusion for 3d printing is basically: looks great, is fast but my models fail to print correctly for some reason.

Can't wait for freecad to get a useable UI, because it is works fairly well for printing despite its UX shortcomings

My email's in my profile. If you have some examples of what didn't work well for you, I'm happy to have a look and see if I can get you unstuck and headed to success.

If it's a calibration issue on the printer (parts print, but are slightly the wrong size), I can recommend Teaching Tech's intro here and here:

https://teachingtechyt.github.io/calibration.html

https://www.youtube.com/watch?v=rp3r921DBGI

If it's in the Fusion->STL stage, I might be able to be of more help. If it's in the STL->physical part stage, the above or other 3DP videos might help.

I wiped the computer used for this whole ago, but the models are probably on the cloud somewhere.

My problem was that the produced STL had some errors that were hard to see but definitely showed up in prints, for example a wall section could be missing.

are you certain the STL stage had the error?

In the 3dp discords i'm a part of it seems that i'm continually reminding everyone that slicer features are usually the culprit. Features like 'detect thin walls', 'ensure vertical thickness' and 'extra perimeters if needed' can and will very quickly ruin a print where the STL is error-free.

That said, one can accomodate these features by modifying the STL so that the slicer transformation occurs in such a way that allows a usable product, but as far as where the error is introduced, 9 times out of 10 it's the slicer.

What should happen is that the slicer should err out to the user when the shape of the end product is predicted to be radically different than the request, but I haven't ran into such features yet. Most slicers just happily try to print stuff that is physically impossible to do, and might be radically different than the shape of the STL -- usually resulting in a plate of spaghetti if you're using an FDM machine.

Your slicing software should warn you if the model is non-manifold.

https://www.instructables.com/id/Non-manifolds-Your-Worst-3D...

Yeah, but there question is why fusion360 created such files. Similar designs in other tools worked just fine.

I've some years of experience with CAD and know often what causes such issues but in the case of fusion360 I just couldn't figure out why this happened - in sometimes extremely simple models.

I haven't used fusion360 for about a year so maybe they have fixed the bugs now.

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