Makerbot Replicator: State of the badass art

Ars Creative Director Aurich Lawson has been sitting on an Ars-owned Makerbot Replicator 2 and several boxes of colored filament for months, waiting for a chance to do something fun with them. It took a bit of cajoling, but I got him to ship me the unopened printer and the filament. A day later, the box was sitting in my foyer.

The Makerbot Replicator 2 is in many ways the opposite of the Printrbot. It's a $2,200 device instead of a $299 device, and it's designed to essentially be a turnkey 3D printer that an average person can use without having to get into its guts and tweak it to death. After pulling it out of its box and getting it set up, I was immediately struck by how different it felt—the Replicator 2 looks and feels like something you can leave running without it potentially burning down your house. It even has a neat little spool-hanger on the back where your filament spool can sit and unroll itself (unlike the Printrbot, where tangling filament was a constant problem).

The Replicator 2 is much larger than the little Printrbot Simple, as the above image shows. The Printrbot can sit comfortably on the Replicator's build plate with plenty of room to spare. The Replicator's X and Y axes are driven by tensioned belts instead of relying on pulleys and string; this close coupling of head to motors enables the Replicator 2 to make much finer X and Y movements than the Printrbot. The vertical Z axis uses worm gears and threaded rods, as with the Printrbot, except here the print surface moves, not the head.

Rather than a wooden platform, the Replicator comes with a nice acrylic build place, embossed with a lot of little Makerbot "M" logos. When you first turn the Replicator on, it guides you through the process of installing the build plate in its plastic clips. Next it takes you through the one bit of tweaking you need to engage in: leveling the build plate. Just as with any home 3D printer, the nozzle height is very important, so the Replicator positions the nozzle at several places on the print bed and has you slide a thin paper card (which the company supplies in the packaging) beneath the nozzle to get the height set correctly.

Once the build height is set, you load up your filament and you're ready to fire up the software. The Replicator comes with Makerbot's closed-source proprietary 3D printing application, Makerware. The application is friendly, with big, bold typefaces and a clean design. You pull in your STL files, as with Repetier Host, but once you have them positioned and scaled to taste, you just hit the "Make" button—the application takes care of the slicing for you. Because the application is designed to work specifically with Makerbot 3D printers, there are easy-to-use presets for print quality, too. Higher fidelity printing makes the print head move slower and take longer, but the layers are smaller and the quality of the printed object is visibly higher.

I wanted to give the Replicator a good, thorough test, so the very first thing I printed was a complex model with a lot of overhang. It failed spectacularly. However, Makerware has an option in its print screen to print "supports"—algorithmically constructed structures beneath the overhanging parts of the model, which provide a nice build surface and which also cleanly detatch from the actual model after it's finished printing. I checked the option, and my T-rex began printing.

He took, I kid you not, 22 hours. However, the next day I had a totally awesome 3D printed T-rex, which I immediately photographed attacking the Printrbot.

But one thing bothered me—the T-rex had a very visible, very obvious seam in his upper body, stretching from his back all the way through his head. In fact, I had to superglue his upper jaw on in order for it to stick correctly. I chalked it up to a problem with the 3D model file and eagerly started printing more stuff. The next thing I built was an Aperture Science Weighted Companion Cube so that my T-rex would have some company. This printed correctly, too.

I was emboldened, and I started to think some really unhealthy thoughts about the little $299 Printrbot—things like "Man, you really get what you pay for" and "This is like the 3D printer equivalent of an EZ-Bake Oven." There was a whole slew uncomplimentary things on my mind... and then the $2,200 Replicator 2 simply stopped working.

One minute it was going fine, and the next it quit feeding filament. I had to disassemble the print head and adjust the tension on the little plunger that keeps the filament pressed against its drive wheel, but this didn't really help. Almost as if a switch had been flipped, I couldn't print anything. After a few layers, the Replicator would simply stop feeding through filament and start "air printing," with the head zipping crazily through the air further and further away from the incomplete model, extruding nothing.

The fix for this problem was a brand new extruder—a part which, embarrassingly enough for Makerbot, was inspired by designs created by frustrated and angry Replicator owners who were facing the same problem I was with the original plunger-based extruder (though how those frustrated customers managed to actually print their replacement extruders in the first place is beyond me). Makerbot shipped the upgrade without charging me anything except shipping. A few days later, I eagerly installed the thing and hoped that was the last time I would ever have to tinker with the printer.

It was not to be. In fact, things only went downhill from there.

The new extruder head solved the feed problems, but prints still failed, usually with a clogged extruder head. I built a neat Ars Technica coaster and wanted to print out dozens for my coworkers, but I couldn't (and still can't) get the Replicator to make it through an entire coaster without me having to pause the printing and clear a jam.

After talking back and forth with Makerbot support, I originally thought the issue might lie with a warped build plate. I've printed build plate calibration objects to try to find exactly the right level, but even after spending four hours hunched over, printing leveler after leveler, endlessly twiddling dials, I could not make the plate perfectly level. More searching indicates that this is apparently a common problem with the acrylic plates supplied by Makerbot. After being exposed to the heated filament for a certain number of hours, they warp. The warping is generally very slight, but the individual layers laid down by the extruder head are only one or two tenths of a millimeter thick, and tiny defects across the big build plate can cause tremendous problems. Many folks suggest remedying the problem by buying a perfectly flat glass build plate—and they'll sell you one with the attachment notches pre-cut for only a hundred dollars. However, careful checking with a straight-edge showed no apparent irregularities on the big acrylic slab; Makerbot instead suggested sending me a new extruder tip and thermal barrier tube, which hasn't arrived as of press time for this article.

That same chasm of aftermarket modifications began to yawn in front of me again. This time, I wasn't just annoyed—I was getting legitimately angry. It's one thing for an early-adopter-bound inexpensive 3D printer to have issues. I can forgive that. After all, it's sold in a kit and it's targeted at people who love to tinker. In fact, some folks probably derive a lot of pleasure from that, and good for them.

But the story is a lot different when you're dealing with a $2,200 piece of equipment that is billed as providing a more turnkey experience. The level of tinkering and futzing and calibrating and parts-replacing the Makerbot Replicator has required is inexcusable. This is a product that shipped with an enormous design flaw—the plunger-based extruder—that the community itself had to correct, and it's one that still requires aftermarket upgrades in order to function without constant tweaking.

In the end, the Makerbot Replicator and I reached a sort of uneasy balance. I can still print on it—in fact, I'm on the hook for a bunch of Ars coasters right now—but it requires continual fiddling with the build plate level screws. I have to watch every build like a hawk, sometimes stopping the build three or four times to unload and reload filament to clear a clog. I find I am most successful when I crank the bed way up for the first layer and then crank it half a millimeter further away from the print head—several turns of the finger-bruising screws—for the rest of the object. The larger the object, the more problems it has.

Video: The Makerbot Replicator 2, in a rare display of success, prints Christopher Walken's visage on a cowbell.

Leveling my expectations

And that, perhaps, is my problem. The expansively large bed of the Makerbot Replicator invites exploration—you want to fill that whole damn thing with a gloriously huge 3D printed object. You want to print a giant plastic T-rex and watch it slowly take shape, snarling up at you. You want to build gears and bowls and neat stuff. There's so much it looks like you should be able to do. That invites you to fly too close to the Sun, and then your 3D printed wings turn to melted crap.

I had the best luck with both of these 3D printers when I kept my sights aimed at simple, small things. It's not terribly fun to only print a three centimeter shape. No one really needs to print an infinite number of rectangles or rough spheres, but uncomplicated models like coasters are actually pretty easily done (Replicator clogging problems notwithstanding). The temptation to make big complex models in a single piece is hard to resist, but very few of those work. Properly "building" a complex structure on a 3D printer is a matter of carefully dividing your model into many small pieces and printing each of those individually, then sanding away any print imperfections and assembling it.

In spite of their impressive names, these are not Star Trek-style replicators. These are machines that extrude thin tubes of plastic and draw shapes layer by layer. They are hot, noisy, and slow. They take hours to make small designs (each of those Ars coasters takes two hours to come together), and every moment that they're running is punctuated by the musical robot noise of shifting stepper motors (and fans, in the case of the Replicator).

You can realistically create bracelets, or rings, or useful little plastic widgets. But creating complex structures—like, say, the Liberator pistol—requires a hell of lot more than just loading up a model file and pressing "Print."

How deep does the rabbit hole go?

In the month that I had to play with both printers, I barely scratched the surface. After hundreds of hours on the Printrbot Simple and the Makerbot Replicator 2, I feel like I've gotten a very, very basic grounding in the world of 3D printing. I understand a bit of the terminology, and I even designed and printed my own model (the Ars coasters, which you can download here). A full exploration of the various kinds of 3D printers out there—from the expensive to the totally DIY—would take far more time than I have to devote to the subject.

The takeaways I have from my brief time with the two devices is that the inexpensive Printrbot is actually a hell of a little machine. It's not a great first 3D printer, since making it work well and produce good results requires a whole lot of time, attention, and skill. But $299 in kit form or $399 assembled is a hell of a bargain. It fits very nicely into the niche its creators are carving out for it: it's an inexpensive way to get a good-quality 3D printer out there for those who can't afford a Replicator or something similar. If you pick one up, you can expect to be required to immerse yourself into the world of mods and tweaking, chasing that perfect printing experience forever.

The Makerbot Replicator 2, on the other hand, is both magical and disappointing. When it works, it's awesome. When it doesn't work—which, in my experience is about 75 percent of the time—it's incredibly frustrating. The little Printrbot gets a pass for needing aftermarket tweaks to work properly. The Makerbot Replicator 2, which costs almost eight times as much, gets no such pass. If I paid $2,200 of my own money for this device as it currently exists, I would have long since returned it. The Makerbot folks continued to work with me up until this article's deadline on trying to get the Replicator 2 working correctly, and those efforts are still ongoing, but as of this moment I still have a very expensive machine that wastes a lot of filament with failed prints.

And yet those moments when everything works properly and the Replicator produces a perfectly formed print are magical. The Printrbot, even at its best, produced rough and sometimes saggy prints. The Makerbot Replicator's output is clear and smooth, with sharply defined edges and facets. When it prints, it prints very well. I've got a big dinosaur, a bunch of Ars coasters, some Companion Cubes, and a Walken-embossed cowbell to prove it. It's a wonderful machine—it just feels like it's designed to fail and only manages to print successfully on accident.

Truthfully, I wouldn't buy either of these devices. The Makerbot Replicator is ludicrously expensive for a hobbyist purchase, and the Printrbot requires too much time to get it working right. However, maker-types with an itch to tinker should absolutely consider the Printrbot Simple. For all its flaws, the $299 kit is still a good value.

Just don't expect to be saying "Tea, Earl Gray, hot," any time soon. You might be able to get started on the teacup, though.