A new version of the Printrbot Simple was released this summer, and this sleek new model includes a few highly desirable features. The metal enclosure was improved, linear rails added, a power switch was thrown in, and the biggest feature — a touch screen — makes headless printing easy.
Adding a usable display and achieving reliable WiFi are big engineering challenges, and thanks to the Internet of Things it’s only going to become more common to expect those features. How did the Printrbot team implement this? [Philip Shuster] recently released a write-up of how the Printrbot Printrhub came together.
The story of the display and WiFi module in the newest Printrbot begins about a year ago with a post on Hackaday. [Philip] built the Little Helper, a little electronic Swiss Army knife capable of basic IO, sending out PWM pulses, sniffing I2C, and a few other handy features. The Printrbot team reached out to [Philip], and after a few conversations, he was roped into the development team for the Printrhub.
Departing slightly from the Little Helper, the Printrhub features the same microcontroller found in the Teensy 3, a 2.8 inch TFT display, capacitive touch sensor, microSD card slot, and an ESP-12 module to handle the WiFi connection. The display system was tricky, but the team eventually got it working. Using an ESP8266 as the WiFi module for a printer is more difficult than you would think, but that works too.
One of the more interesting challenges for 3D printers in the last few years is the development of a good printer display with wireless connectivity. Yes, those graphic LCDs attached to an Arduino still work, but a display from 1980 doesn’t sell printers. In just a few months, the Printrbot team came up with a relatively simple, very elegant display that does everything and they’re releasing all the hardware as open source. That’s great news, and we can’t wait to see similar setups in other makes of 3D printers.
Building a big 3D printer has its own challenges. The strength of materials does not scale linearly, of course, and long axes have a tendency to wobble. That said, building a bigbot isn’t hard – stepper motors and aluminum extrusion are made for industry, and you can always get a larger beam or a more powerful motor. [James] is going in the opposite direction. He’s building tiny, half-scale printers. They’re small, they’re adorable, and they have design challenges all their own.
At this year’s New York Maker Faire, [James] is showing off his continuing project of building baby 3D printers. He has a half-scale wooden Printrbot, a half-ish scale Mendel Max, a tiny Makerbot Replicator, and a baby delta and baby Ultimaker in the works.
Click past the break for a gallery, and more info on [James’s] tiny creations.
The Printrbot Simple Metal is a good 3D printer, with a few qualifications. More accurately, the Printrbot Simple Metal is a good first 3D printer. It’s robust, takes a beating, can produce high-quality prints, and is a great introduction to 3D printing for just $600. There are limitations to the Printbot Simple Metal, the most important is the relatively small 150mm cubed build volume.
Increasing the build height on the Printrbot is as simple as adding two longer smooth rods and a single threaded rod to the Z axis. Increasing the X axis is a bit trickier: it requires a very flat sheet that doesn’t warp or bend over 500 mm, even when it’s being supported in different places. [ken.do] is engineering stiffness into a build plate here. The solution to a huge bed is a two kilogram aluminum bed supported by heavier rails and riding on a massive printed bushing block. Does it work? Sure does.
If you want to print tall objects, the current crop of 3D printers has you covered: just get a delta, and you’re limited only by the length of the extrusion used in the body. Creating big objects in all three dimensions is a marginally solved problem – just get a big printer. Big printers have drawbacks, notably the incredible power requirements for a huge heated build plate.
The ability to print long objects is a problem that’s usually not addressed with either commercial 3D printers or RepRaps. We’re glad to see someone has finally realized the limitations of the current crop of 3D printers and has come up with a way to turn a very good first printer into something that solves a problem not covered by other 3D printers.
If you are like us, you tend to do your 3D printing with plastic or maybe–if you are lucky enough to have access to an expensive printer–metal. [Adam Feinberg] and his team at Carnegie Mellon print with flesh. Well, sort of. Printing biomaterials is a burgeoning research area. However, printing material that is like soft tissue has been challenging. In a recent paper, [Feinberg] and company outline a method called FRESH. FRESH uses a modified MakerBot or Printrbot Jr. printer to deposit hydrogel into a gelatin slurry support bath. The gelatin holds the shape of the object until printing is complete, at which point it can be removed with heat. If you don’t want to wade through the jargon in the actual paper, the journal Science has a good overview (and see their video below).
The gelatin is mixed with calcium chloride and gelled for 12 hours at low temperature. It was then turned into a slurry using an off-the-shelf consumer-grade blender. A centrifuge was used to remove most of the soluble gelatin. Printing inks were made with materials like collagen and fibrin. The FRESH process actually uses liquid ink that gels in the gelatin.
The printer uses an open source syringe extruder found on the NIH 3D print exchange (they never say exactly which one, though and we had trouble matching it from the pictures). In true hacker fashion, the printer prints its own syringe extruder using the stock one from ABS and PLA plastic. Then you simply replace the standard extruder with the newly printed one (reusing the stock stepper motor).
The paper describes printing items including a model of a 5-day-old embryonic chick heart, an artery, and a miniature human brain model. Another team of researchers in Florida have a similar system, as well.
We’ve talked about bioprinting before and even mentioned how to make your own inkjet-based bioprinter. The FRESH method looks like it is in reach of the hacker’s 3D printing workshop. We cringe to think what you will print when you can finally print body parts.
We’ve seen a lot of experimenting with 3D printers over the years, and that is a good thing. However, [Tyler] has had a bad experience with experimenting. He has a Printrbot Simple Metal and decided to try nylon weed wacker line. Since he wanted to get straight to printing, he skipped the apparently important step of drying the trimmer line before printing. This experimentation ended in several clogged nozzles. Removing and cleaning the nozzle several times put undo stress on the Ubis hot end wires and they broke. Things were not going well.
In an effort to make his printer more repairable, [Tyler] ordered up an aluminum RepRap heater block, heating resistor and thermistor. The heater block was tapped with standard M6 threads but the Ubis was 1/4 inch. This was remedied by drilling and tapping the M6 hole to 1/4-20.
Now for the nozzles, [Tyler] bought a handful of cheap brass acorn nuts. He drilled a hole for the molten plastic to exit the nozzle, then used a Dremel to grind the acorn nut’s dome into a cone. He reports it only took him about 5 minutes per nozzle.
It looks like [Tyler] got back to printing with a little creative thinking. Unfortunately, the Ubis and J-Head hot ends are not interchangeable. A couple of other ex-Ubis users have made J-Head adapters for their Printrbots.
Hackaday is getting back into the swing of doing reviews, and with that comes reviews of the tool du jour, 3D printers. I have some reservations about reviewing a 3D printer; they’re a new technology, and what may be standard today could be hopelessly outdated in a few months time. Remember geared extruders? The new hotness is, apparently, direct drive extruders.
This is a review of the Printrbot Assembled Simple Metal. If you need any evidence that reviews of 3D printers have a shelf life, you only need to look at the Getting Started guides for this printer. When I bought my Simple Metal, the Printrbot recommended software stack was Slic3r and Repetier-Host. Barely three months later, Cura is now the Printrbot recommended software stack. If you think a simple change in software is inconsequential, check out these prints:
The print on the left was sliced with Slic3r. The print on the right was sliced with Cura. Notice the small teeth that grip the timing belt on each of these prints. With the Cura-sliced print, everything is fine. The Slic3r-sliced print is a complete failure, not of the machine, but the recommended software for the machine.
Therefore, if the goal of writing a review is to have a definitive opinion of a piece of equipment, a number of questions must be addressed. Since most 3D printing software is open source, should software be included in the review? Is the value proposition of a 3D printer simply a function of price to build volume (this seems to be the standard metric now), or are there intangibles? Should the review cover the quality of prints out of the box, or should the review only focus on print quality after dozens of hours of tweaking? I simply don’t know the answers to these questions, and I suspect you couldn’t get any two people to agree on the answers to these questions.
With that said, I feel I have used this printer enough to make a judgment call as to if this printer was a good buy.
So, you’re thinking about finally buying a 3D printer? All the cool kids have one. Plus, how hard can it be anyways? Well, before you pull the trigger, it might be best to read this cautionary tale of one user’s experience in getting started with his first 3D printer.
[Scott Hanselman] is a programmer and teacher who started out with zero knowledge of 3D printing. In his informative (and somewhat humorous) blog post, you can follow along with [Scott] hour-by-hour as he unravels the some of the common mysteries that almost everyone will encounter with their first 3D printer.
His adventure begins with the frustration of z-axis calibration, an important part of any 3D printer. Some of the newer printers are automating this step (as well as bed-leveling) with sensors and clever software, but even then it might need small tweaks to lay down the all-important first layer. By hour five with his new printer, this slight annoyance turns into disgruntlement, as he finds that although there is tons of documentation on-line, a lot of it can be outdated or simply unhelpful.
In the end, [Scott] got his printer up and running, and learned a lot along the way. We bet you can too – with a little effort that is. As the quality of printers on the market keeps going up, and the price continuing to fall for an entry-level printer, now might be the perfect time for you to get started. But you might want to read [Scott’s] journey to help manage your out-of-the-box expectations.