By no means the first printable robot on Thingiverse, but this one is definitely a charmer.  I mean look at that elegant design!  3-DOF (Degrees Of Freedom) is a lot less than the “classic” hexapod design, but that can be a good thing, after all, think of how much easier to program this would be!

There’s plenty of spaces on this that’d probably be compatible with those nice printable battery packs from earlier.  3D printing once again proves itself as a great tool for geeking out with robots!

Not a terribly surprising result, a lot of highly educated visitors though!  I decided I could use this survey as a bit of a benchmark to get an idea of what kind of crowd I was teaching to.

Given that 3D printing, especially home 3D printing is so geek-dominated, it’s not much of a surprise that most of us are coming to 3D from the engineering domain.  It’s nice to see that we have a strong contingent of artists from the more purely digital realm joining though!  We need all the cool game tanks and animated characters we can get!

Probably reflecting the large number of engineers, is the solids vs meshes divide.  I’ll continue to provide some tutorials on both sides of the fence here, since both have strengths, and also since there’s yet really for anything like a One Tool To Rule Them All in this field, although OpenSCAD is certainly a big hit on Thingiverse.

Because that’s an active circuit you can CNC print.

Obviously this is one of those projects in early infancy, but printing active devices, even simple ones, is a major bootstrap inflection point for the world of digital fabrication.  When you can print electric traces and semiconductors, a lot of things change.  Obviously, this is a long way from printing out the kind of high-density computronium you get from TSMC, IBM and Intel, but you do get some nice benefits.  For one, no fab plant to send parts to.  While it’s entirely possible to fab low tech devices in, say, a pizza oven, organic semiconductors are going to be a better path for DIYers, due to the dramatically reduced overhead (if higher per-unit cost) and due to the lack of an anneal, which can be pretty hard to do with a pizza oven.  Also, all-low-temperature manufacture means you can mix the fabbing process with plastics and other, ah, delicate materials.  Including biocompatible ones.

Expensive, clunky, and issue-prone today, but potentially a low-cost in-your-garage way to string the connective wiring, lights and other doodads between your semiconductor computer chips in the future of home digital Making.

I’ll admit it, I think I started writing tutorials like a Blender Manual Page for a bit there, which honestly the Blender Foundation can do better than I can.  Additionally, the survey results have me thinking of a number of better directions I could be taking this.  So hang in there, I’m going to re-tool this entire path as a set of examples, possibly involving some video tutorials, around a modeling task rather than around the software.  I’ll start from an “out of the box” Blender installation, customize it for solid design (activating the plugins for gears and other goodies mostly) and then go about creating something mechanical, probably along the lines of a gearbox, using real-world measurements (with calipers even!) and hopefully acting as a quickstart guide with a purpose, rather than Yet Another Tutorial By Someone Who Doesn’t Get Why Everyone Hates Blender.

Also, the OpenSCAD tutorials will definitely continue, because where Blender is actually pretty well served as a program in terms of tutorials (even if a lot of them will needlessly focus on things like texturing that don’t matter if you’re going to 3D print them), there’s precious little for OpenSCAD, although I highly recommend the wiki.

So OpenSCAD is a big deal– it’s a tiny 7mb download that gives you the world of constructive solid geometric modeling in the form of something that looks at least a fair bit like C, and is modular and scalable to pretty complex geometry.  However, it’s kind of got the, uh, opposite problem of Blender.  Where Blender looks kind of like a space station, bristling with buttons the minute you open it, OpenSCAD looks like this:

It’s pretty much a blank page.  However, modern versions of OpenSCAD, like Processing and the Arduino environment, come with examples, pre-linked in the file menu.  However, if you’re a 3D newbie or just haven’t done much with solid geometry, even the first example file is maybe a little daunting at almost half a page, with rotations and intersections and stuff.  We’ll start with the simplest file that will render, export, and print.  Ready?

cube(40);

Riveting, right?  That’s a 40mm cube sitting with one corner on the origin.  (You can go to the View menu to show the origin, which can be really helpful.)  If you hit F5, OpenSCAD will display this cube in the window on the right, and you can drag in that window to rotate the view around, and roll your scroll wheel to zoom.  Pretty easy, and fairly boring.  Let’s make this one step more complicated to get a compound shape:

union(){
cube(40);
translate([10, 10, 30]){cube(20);}
}

This file has two new operations: translate and union.  Once you’ve typed or copy-pasted this into your window, hitting F5 will give you a cube with a bump on the top.  This is done with two new operations, so let’s tackle them one at a time.  First, the translate operator.  The translate operator takes a triplet of numbers (also known as a 3D vector) which moves the contents of the brackets after it in three dimensions by the three numbers stated.  Inside the brackets, we’ve put a cube of size 20, which starts like the first one with its corner at the origin, but is then moved by the translate operator ten units right, ten units forward, and thirty units up.

Surrounding both cubes in the descriptive language here is the union operator, which binds these two cubes together as one object so that when the file is rendered to an STL file, it will seamlessly combine these two cubes into one object.  (This isn’t a hard object to model in Blender, but when you’re unioning a lot of objects Blender will kick up its legs and die where OpenSCAD will keep chugging merrily along.)

If you replace the word union with the word difference here, you’ll get the difference operator, which cuts the second cube out of the first.  Union and difference operators are basically the core of how this geometry tool works, and you can get a lot done with just those and the cube, sphere and cylinder primitives.  Here’s a simple file that makes use of all three primitives to get you started with them:

union(){
cube([40,40,4],true);
cylinder(40,15,5);
translate([0,0,40])sphere(10);
}

The cube primitive here has been given a vector instead of a single number, which allows you to make it any rectangular solid rather than a simple cube.  The “true” keyword at the end of either a cube or a cylinder statement sets the primitive to start centered on the origin.  (This is all the free translation you get though, after that you must use the translate command.)

So hopefully this was simple enough for those new to 3D and CSG but had enough content to get you properly started– the surveys so far seem to indicate there’s a lot of desire for extremely simple examples so hopefully this fits the bill.

Lovely little wrench here.  Print to fit!  I love how minimalist this design is.  Gets the job done, no frills, tidy-looking design.  Also has a very materials-honest look overall.  Cooperating with the material makes for much prettier designs a lot of the time.

OpenSCAD was a clear favorite, so I’ll be refreshing myself on this to try and get some OpenSCAD tutorials made soon.  Blender however also seems pretty popular, so I won’t be abandoning it either.  I will also try to bring up other tools as I learn more about them and as uses occur to me!

Mostly the interest for new Blender tutorials was in the basics, getting around the (good but very weird) interface and making things with it.  In the Other field there was a neat suggestion: mechanical motion simulation!  It can be done, and while it’s by no means easy it might actually be worth a look.  (Long story short, look up stuff on the physics and game engines…)

As I expected, most of you are still looking mostly to mechanical design– home 3D printers are still very much for-tinkerers-by-tinkerers, so a lot of what we’re after is mechanical widgets.  One response from the other category that stuck out here: mechanical example from measurements.  I’ll definitely give that a shot!

One of the more consistently overpriced-feeling components in electronics are the battery packs, single pieces of injection plastic with perhaps a paperclip worth of metal, sold for several dollars when bought at the corner electronics depot, which just seems like a lot of money to pay for something that seems an awful lot like you could print it…

But now of course now, all you need is your trusty 3D printer and some rudimentary metalworking skills and you can spin your own!  The parametric battery pack just needs some metal contacts and it’s good to go.  Because it’s OpenSCAD, it can be bolted onto your existing robotics project with ease!  (And apparently Hack a Day liked this one too!)

Over the weekend, someone created a Wikipedia entry for Thingiverse. We were flattered, except of course the Wikipedia team immediately flagged us as ‘speedy deletetion’. Sadface! If my wiki-memory is correct, we’re not supposed to edit our own entry. If there are any Thingiverse users out there who feel like we should have a wikipedia entry, please feel free to head over to the page and make a case for the site to page to stay up.