I design all of my parts (mostly camera/lens accessories and quadcopter frames) in OpenSCAD.

http://www.openscad.org/

Not really a good candidate for a general-audience "easy to use" 3D design program (and thus doesn't preclude their plan to build something like that), but likely highly relevant for any HN readers who are looking for such a thing who are comfortable with code/markup and are wired to be able to pre-visualize things in their head prior to building them.

There are off-shoots like OpenJSCAD (see: http://openjscad.org/) as well, which actually give you more of a complete language. The OpenSCAD language is really simple and is more like a markup language with some limited flow-control than a real full-blown programming language -- but I kind of like it that way, and if you need to get really algorithmic with your designs you can always generate OpenSCAD "code" from other languages (of your choice) since it is all just text.

Designing and printing a 3D object is fundamentally much more complex than typing out an essay and hitting print. There's always going to be a big learning curve for someone trying to get into 3D printing/modelling for the first time. There's no way to get around that, it's especially hard for people who do not have a lot of spatial reasoning experience.

The most important point in the article, and I think the most valuable potential feature of new 3D printing oriented design software is this:

Communication of 3D printing limitations to the user at design time

For someone experienced with 3D printing (someone who's messed up a few prints and thought about why) it's easy to see why certain features are unlikely to print correctly because they have had the opportunity to build a mental model of the 3D printing process in their head. Helping people build up this mental model quicker, especially without having to actually print and iterate physically is invaluable to being able to efficiently design 3D parts.

I'm surprised they don't mention OpenSCAD [1], which in conjunction with a decent vector graphics editor works wonders for a wide range of objects.

Yes, it has a programming interface, but I'd argue the visual/spatial context makes it much easier to pick up than most programming languages. I've seen it successfully taught to people who otherwise have little to no coding experience.

(If I had to gripe about something in OpenSCAD, it would probably be lack of spline support.)

[1] http://www.openscad.org/

Not sure what the author means by "freeform". He seems to use that term to refer to mesh editors, which do surfaces for graphics, vs. solid geometry editors, which understand volumes. Mesh editors are more for 3D graphics.

Learning to use a constructive solid geometry system used to be hard, but Autodesk came out with low-end tools based on their their Inventor product line which make it easier. There's 123D, 123Make, 123Sculpt, Meshmixer, etc. The heavy CSG machinery of Autodesk Inventor is inside, but it's not dumped on the user all at once.

We used to teach little children to use OpenScad years ago along with programming(I volunteered for that). Kids learn fast.

Now we teach them FreeCAD, and python scripting for the advanced ones.

I have no idea what the author is talking about, designing a 3d editor is not trivial, most kids don't need very advanced 3D editing either. They will just ask the one who is good at it, or download it from the Internet from already made models.

There is a need for 3D curves in the Open source world. This will be worked on over time.

"The problem is that these requirements are not communicated to the user during the modelling process, so the model that the user designs is not well optimised to be printed, and must often be fixed with other software."

I couldn't agree more - finding out your design won't work after you've manufactured it is sort of like finding out your code won't compile after you've deployed. There needs to be better feedback during the design phase to make hardware as easy and fast as software.

This is exactly the problem we're trying to solve at Plethora, albeit with CNC milling instead of 3D printing. We have an add-in for 3D modelling programs that tells you manufacturability issues in real time as you design.

For those who are interested, check it out here: https://www.plethora.com/how

For parametric CAD, there's Solvespace. GPL'd as of version 2.0. I like it better than OpenSCAD, and the price is equally right. I don't know why, but it doesn't get much attention.

http://solvespace.com

I thought Tinkercad's goals were for 3d printing. No idea if it actually meets the criteria

https://www.tinkercad.com/

There's also Clara.io but I think it's targeting rendering

https://clara.io/

We use SolidWorks at my school, and my students don't seem to have any issues. It's fairly easy to use and easy to generate files that our 3d printer can handle.

AutoDesk has 123D Modeler[1]. I'm not sure which printers it works with, but it probably uses the Spark platform[2] for the actual print drivers.

    [1] http://www.123dapp.com/design
    [2] https://spark.autodesk.com/

I tried 3D printing for the first time this year, and I used Blender. It was as easy as exporting an .STL file and uploading it to Shapeways.

http://moi3d.com/

Sounds interesting. When do you expect to launch ?

Another alternative I saw at the Maker Faire last weekend. http://www.sketchup.com/