We’re planning a Nerdy Derby event at Maker Faire Milwaukee, and like last year, I wanted to 3D print a bunch of wheels, and yes, it is fun designing strange wheels. Most of my designs this year are refinements from last year, and I wish 3D printing were as simple as hitting “print” and walking away, but that’s not always the case.
I found that if I printed one object, it worked fine. If I tried multiple objects, things were failing, either with one or more objects, or everything. I’d try to print two wheels at once, and one would work, the other would fail. Slic3r allows you to generate the G-Code needed to print files, and has an option to print multiple objects, either by printing them all at once, or one at a time. Both of those options just weren’t working for me, for whatever reason. (My 3D printer is a RepRap I built myself, and yes, it has issues now and then.)
But you know the old saying… if you can’t fix it in hardware, fix it in software! So I did… You’ll notice that the image above shows four wheels with a small square connecting them. I ended up pulling an STL file into OpenSCAD (my favorite 3D modeling application) and then duplicating it four times and adding a small 1mm tall square between them to connect it all into what the printer would see as one single object.
It worked! I’m now seeing much more success with printing, and getting sets of 4 wheels connected with a thin piece of plastic that’s easy to remove. Oh, I should also mention that our friends at Inventables were kind enough to donate some filament to this cause, so if you have fun building a car with 3D printed wheels at Maker Faire, be sure to stop by the Inventables booth and thank them for making it happen.
(BTW, MegaMag is printing way more wheels than I am, and going 40-Up!)