Designing 3D Things – Easily!

One of my major problems with 3D printing has always been that I’m put off by the amount of time and effort required to learn the 3D modeling skills necessary to create my own original objects.  Yes, I *could* just keep printing other people’s designs off of Thingiverse, but I got my fill of that last winter when I helped run the library’s 3D-print-on-demand service.  After a while, it begins to feel like work.

So when Sharona told me a few weeks ago that she’d heard about an app that could turn 2D drawings into 3D models that we could print, I got really excited.  By the end of the day, she’d installed MakerBot’s Printshop mobile app on an iPad and we’d gone through the process of snapping a photo of something I drew, choosing how thick to print it out, saving it to our library in the MakerBot cloud, opening it up on the computer attached to our MakerBot, and printing it out in plastic.

Although you’re creating a 3D model of your drawing with Printshop, you’re still going to end up with something essentially flat.  You can think of it like using a cookie cutter.  Your drawing becomes the cookie cutter, and the app lets you choose how thick or thin you want your “cookie” to be.  You can also choose to print out just an outline of your drawing, with or without a back.  (While we’re thinking about cookie cutters… this would be an extremely simple way to design your own.)

Of course, there are ways around just about any problem.  I wanted to take those flat objects I could make with Printshop and turn them into something *really* 3D.  If you watch enough cooking shows on tv, sooner or later you’ll see someone who cuts out their cookies into interlocking shapes that fit together to create a sculpture: a gingerbread house, maybe, or a dragon.  I wanted to do something like that using Printshop, so I set out to design a turkey I could take home with me for Thanksgiving.  Here’s what I learned in the attempt:

1. Work with blank paper (or another unmarked surface)
    
   I drew my turkey first on notebook paper, because that’s what I had on hand, and then traced it onto plain printer paper.  Ultimately you will need to get your design onto some sort of plain-colored surface like printer paper, because Printshop is easily confused by extraneous lines or markings (including what shows through the paper if you have something written on the other side).The last photo above shows my turkey’s body in Printshop, with some extra markings that came along with it.  You can delete those so they don’t print, but I had some trouble selecting them in order to do so.  Basically, it was a pain.  Also, sometimes just having more markings–even if they were intentional–seems to confuse the app.  My original tail design included hatch marks on the feathers to give them some texture.  I had to redraw a plainer tail so that Printshop could handle it.
2. Your life will be easier if you prototype with cardboard
   
   I thought I could get away with just drawing out all my pieces and taking pictures of them with the app… but I shouldn’t have.  I redrew the turkey’s feet umpteen times, and I still don’t think I actually designed them such that they’ll ever fit together correctly.  I really think all my pieces would gone together much better if I’d done a version of this thing in cardboard first so I could really understand how big all the slots needed to be in order to support various pieces.
3. Don’t assume that everything scaled properly when you photographed it
   
   Because you can’t photograph all the parts at once, and because human beings aren’t so great at holding the camera at *exactly* the same height every time we take a picture, odds are that your scaling has gotten messed up in the process of digitizing your object.  Get out your ruler and figure out exactly how long each piece ought to be!  Then make sure that you set all the pieces to those exact sizes in MakerWare.  (Or at least make sure you’re preserving the right size ratio of each piece to the others.) I skipped this step and said, “Oh, that looks about right.”  I wish I hadn’t.
4. Keep an eye on your printer while it’s printing, especially if you’re in a hurry
   The sad truth is that if you live in the northern hemisphere and your printer has to cope with drafts, we are back in the season of warped prints.  My turkey print warped to the point where the printer’s nozzle clogged and the print ended up failing.  I hadn’t left myself enough time to try the print over again before I left for Thanksgiving.  I didn’t get to take a 3D-printed turkey home with me for Thanksgiving after all.
5. Admire your work, even if it’s a failure
   
   My turkey has a lot of issues.  It’s not as thick as it should be, because the print failed partway through.  It can’t stand on its own because some pieces didn’t scale properly and others weren’t designed well enough to begin with.  Through building it, though, I learned a lot about designing 3D things using Printshop.  When I apply everything I learned to the next thing I try to make, I am going to come up with something totally awesome–just you wait!  In the mean time, I’m pretty fond of my turkey, too, even if it isn’t a total success.