printrbot GO – 8 mm rods, GT2 belts, a belt tensioner and a cooling fan

So after my last round of functional but peripheral upgrades (getting all the tools into handy locations) I decided it was time to focus some time and effort on the printing performance of the bot (an idea that felt almost novel after all of the aesthetic mods I'd otherwise been consumed by recently). It was clear to me that the motion in the Z direction could use some refinement because the x-axis carriage seemed to wobble back and forth a little bit when raising or lowering the extruder manually. Read more [...]

printrbot GO – shoes and a socket

So after months of laboring over these little guys, I was finally satisfied enough with the results I was getting to print out a set of four corner protectors for the bottom corners of the GO. I printed these out in a single print and arranged them all so that the insides of the corners were facing each other (to minimize tool moves over the exterior perimeters) and so that they were aligned diagonally on the print bed (for no good reason). Printing them diagonally was Read more [...]

corner protectors in OpenSCAD (6)

Don't just jump in here, start from Part 1! Now it's time for the big finish. For our final decorative flourish, we're going to put a large rounded corner on each of the three surfaces with screw holes in them, with the radius of the corner determined by how close the screw hole is to the edge. To do this we'll need to learn a little about rotate_extrude however, one of the niftier if also more confusing OpenSCAD functions I've had the pleasure of using. And by the way, if you know a little something Read more [...]

corner protectors in OpenSCAD (5)

Don't just jump in here, start from Part 1! So we've basically got fillet edges on our piece now, but you'll notice that the actual corners are sharp and not so great looking. To make the corners look consistent with the edges, we'll need to subtract the exterior of one quarter of a sphere from the corner in the same way we subtracted the exterior of one quarter of a cylinder to get the fillet edge. The code to do such a thing looks like this: difference () { translate([-pad, -pad, -pad]) Read more [...]

corner protectors in OpenSCAD (4)

Don't just jump in here, start from Part 1! So now that we have some screw holes in our protector, it's time to make it pretty. As with many things in life, the last few steps that take the design from functional to aesthetically pleasing are a lot more work than the ones preceding them, but perhaps more fun to see come to life also. A fillet is essentially a curved edge. As far as OpenSCAD is concerned, it's helpful to think of creating this curved edge by subtracting from our object one Read more [...]

corner protectors in OpenSCAD (3)

Don't just jump in here, start from Part 1! So far we've got a single object in place with two tweakable variables and a little bit of basic OpenSCAD code under our belt. It's time now to learn some new commands and a very handy new concept: the module. We'll use rotate, union and a module call to add screw holes with head recesses to our drawing. The first thing we'll want to do is define a few new variables related to our screw dimensions and placement. Not knowing what kind of screws Read more [...]

corner protectors in OpenSCAD (2)

Don't just jump in here, start from Part 1! By the way, if you're already convinced and serious about learning OpenSCAD, just Google "OpenSCAD tutorial" and you'll find some great options out there. This is as much an exercise for me in "learning by teaching" as anything else. That said, anyone still left in the room can join me in making a "corner protector" (I seem to sometimes call it a "corner support" without rhyme or reason). So to start making our corner protector, open OpenSCAD Read more [...]

corner protectors in OpenSCAD (1)

I keep calling these GO corners because my plan is to print them out and attach them to the corners to make the Printrbot GO a little more travel sturdy. The truth of the matter is though, not even having the kit in my hands, much less the assembled bot, I have no idea if they'll fit. Not knowing the size that will be aesthetically pleasing relative to the overall size of the "suitcase", the thickness that will be required to protect any switches or protrusions, how far from the edge the screws Read more [...]

a book on 3d printing and why you need OpenSCAD

  If you're a coder already, you're gonna love OpenSCAD. When I mentioned to a friend I was thinking about messing around with OpenSCAD, I had never seen it used before, I had only heard mention of it as a powerful open source 3d CAD program. When he sent me back an email with his first OpenSCAD project and it looked like the code from a computer program, I was frightened and confused. And literally laughed out loud. Two things then happened that made me take a serious look at it. 1.) Read more [...]