Giant 3D Printer For Giant Projects

December 18, 2019 by Danie Conradie 21 Comments

Established FDM 3D printers designs generally lead themselves well to being scaled up, as long as you keep frame stiffness, alignment and movement in mind. [Ivan Miranda] needed a big printer for his big projects (videos below), so he built his own i3 style printer with a 800 mm × 500 mm usable print bed and about 500 mm vertical print height.

The frame of the new machine is built using 20×20 and 20×40 aluminium V-slot extrusions with some square tubing for reinforcement. To move all the weight, all 3 axes are driven by double NEMA17 steppers, via a DUET3D board with an expansion board for the extra motors. The extruder is the new E3D Hemera with a 0.8 mm nozzle. The print bed is a mirror, on top of the aluminium plate, headed by a large silicone heat pad. The first bed version used a smaller heat pad directly on the back of the mirror, but it heated up unevenly and the mirror ended up cracking. Look out for the ingeniously lightweight and simple cable management to the extruder. When all was said and done he printed a 800 mm long size 66 wrench as a test piece with zero warp, which is pretty good even for PLA. This project is also a perfect example of the power of 3D printing for rapid iterative development, as lot of the printed fittings went through multiple versions.

Although [Ivan] received most of the components for free, a printer like this is still within reach of the rest of us. We look forward to a lot of big prints by [Ivan] in his signature red, like a massive nerf gun and the ridable tank he is currently working on. Continue reading “Giant 3D Printer For Giant Projects” →

Humongous 3D Printer Produces Boat And Challenges

December 17, 2019 by Danie Conradie 27 Comments

We’ve seen some pretty big polymer 3D printers, but nothing quite as big as the University of Maine’s 3D printer with a 22,000 ft³ (623 m³) build volume. It holds the Guinness World Record for the largest polymer 3D printer, and with that size comes some interesting challenges and advantages.

You might have already seen the video of it printing an entire patrol boat hull in a single piece, and would have noticed how it printed at a 45° angle. Due to the sheer weight and thermal mass of the print bead, it cannot bridge more than an inch, since it’ll just sag. A 45° overhang angle is about all it can manage, but since the layers can be tilted at that angle, it ends up being able to print horizontal roofs with no support. A 10 mm nozzle is used and the extruded line ends up being 12.5 mm in diameter with a 5 mm layer height. The boat mentioned above was printed with carbon ABS, but it can reportedly use almost any thermoplastic. It looks like the extruder is a screw extruder from an injection moulding machine, and is likely fed with pellets, which is a lot more practical than filament at this scale. Check out the video below by [Paul Bussiere] who works in the Advanced Structures & Composites Center at the University. He also does a very interesting interview with his boss, [James M. Anderson].

The 45° layer angle is very similar to how some infinite build volume 3D printers work. For something more within the reach of the average hacker, check out the tool changing Jubilee.
Continue reading “Humongous 3D Printer Produces Boat And Challenges” →

Prusa Dares You To Break Their Latest Printer

December 16, 2019 by Tom Nardi 158 Comments

Two months after its surprise reveal at the 2019 East Coast RepRap Festival, the Prusa Mini has started shipping out to the first wave of early adopters. True to form, with the hardware now officially released to the public, the company has begun the process of releasing the design as open source. In their GitHub repository, owners can already find the KiCad files for the new “Buddy” control board and STLs for the machine’s printable parts.

But even so, not everyone feels that Prusa Research has made the Mini as “open” as its predecessors. Some concerned owners have pointed out that according to the documentation for the Buddy board, they’ll need to physically snap off a section of the PCB so they can flash custom firmware images via Device Firmware Upgrade (DFU) mode. Once this piece of the board has been broken off, which the documentation refers to as the Appendix, Prusa Research will no longer honor any warranty claims for the electronic components of the printer.

For the hardcore tinkerers out there, this news may come as something of a shock. Previous Prusa printers have enjoyed a fairly active firmware development community, and indeed, features that started out as user-developed modifications eventually made their way into the official upstream firmware. What’s more, certain hardware modifications require firmware tweaks to complete.

Prusa Research explains their stance by saying that there’s no way the company can verify the safety of community developed firmware builds. If thermal runaway protections have been disabled or otherwise compromised, the results could be disastrous. We’ve already seen it happen with other printers, so it’s hard to fault them for being cautious here. The company is also quick to point out that the installation of an unofficial firmware has always invalidated the printer’s warranty; physically breaking the board on the Mini is simply meant as a way to ensure the user understands they’re about to leave the beaten path.

How much support is a manufacturer obligated to provide to a user who’s modified their hardware? It’s of course an issue we’ve covered many times before. But here the situation is rather unique, as the user is being told they have to literally break a piece off of their device to unlock certain advanced functionality. If Prusa wanted to prevent users from running alternate firmware entirely they could have done so (or at least tried to), but instead they’ve created a scenario that forces the prospective tinkerer to either back down or fully commit.

So how did Prusa integrate this unusual feature into their brand new 32-bit control board? Perhaps more importantly, how is this going to impact those who want to hack their printers? Let’s find out.

Continue reading “Prusa Dares You To Break Their Latest Printer” →

Feeding Both Filament And Electrons Through A Custom D-Sub Connector

December 13, 2019 by Danie Conradie 28 Comments

We sometimes forget that 3D printers are just CNC platforms with a hotend attached, and there a whole range of alternative tool heads to use. [Jón Schone] has been doing exactly that, and needed a way to quickly disconnect his hotend completely from his printer, so he 3D printed his own custom D-sub connector for both filament and wires. (Video, embedded below.)

[Jon] has added a number of upgrades for his Creality CR10 3D printer, including a quick change tool mount to allow him to also use a laser engraver and even a small spindle. When the hotend is removed there’s no way to quickly disconnect the wiring , so the print head is usually left connected and placed to one side of the printer. For a quick detach solution for both wiring and the Bowden tube, he first modified an off-the-shelf D-sub connector. The connector was relatively expensive, and the tube had a tendency to pop out, which led to some failed prints.

[Jon] wanted to use proper Bowden tube fittings inside the connector, so he designed and printed his own D-sub connector and bought loose contacts. Pushing the contacts into the housing turned out to be quite difficult to do without breaking them, so he’s working on making that process simpler. This is just one of many examples of 3D printing 3D printer upgrades, which has been a core feature of the RepRap project right from the beginning. Check out the video after the break

We have no shortage of 3D printer hacks and there will be many more to come. Some cool recent ones includes the Jubilee CNC that was built from the start with automatic tool changing in mind, and a printer that fits in your backpack. Continue reading “Feeding Both Filament And Electrons Through A Custom D-Sub Connector” →

Supercon SMD Challenge Gets 3D Printed Probes: Build Your Own

December 12, 2019 by Al Williams 2 Comments

This year was the second SMD challenge at Supercon, so it stands to reason we probably learned a few things from last year. If you aren’t familiar with the challenge, you are served some pretty conventional tools and have to solder a board with LEDs getting progressively smaller until you get to 0201 components. Those are challenging even with proper tools, but a surprising number of people have managed to build them even using the clunky, large irons we provide.

During the first challenge, we did find one problem though. The LEDs are all marked for polarity. However, since we don’t provide super high power magnification, it was often difficult to determine the polarity, especially on the smaller parts. Last year, [xBeau] produced some quick LED testers to help overcome this problem. This year we refined them a bit.

As you can see, the 2018 model was a very clever use of what was on hand. A CR2032 holder powered the probes and the probes themselves were two resistors. If you can get the LED to light with the probes you know which lead is the anode and which is the cathode. A little red ink makes it even more obvious. Continue reading “Supercon SMD Challenge Gets 3D Printed Probes: Build Your Own” →

Are You Getting Your Money’s Worth From Threaded Inserts?

December 12, 2019 by Dan Maloney 14 Comments

Have you ever wondered whether it’s worth the time and expense to install threaded inserts into your 3D-printed projects? [Stefan] from CNC Kitchen did, and decided to answer the question once and for all, with science.

If this sounds familiar, it’s with good reason: we covered [Stefan]’s last stab at assessing threaded inserts back in March. Then, he was primarily interested in determining if threaded inserts are better than threads cut or printed directly into parts. The current work is concerned with the relative value of different designs of threaded inserts. He looked at three different styles of press-in inserts, ranging in price from pennies apiece to a princely 25 cents. The complexity of the outside knurling seems not to be correlated with the price; the inserts with opposed helical knurls seem like they’d be harder to manufacture than the ones with simple barbs on the outside of the barrel, but cost less. And in fact, the mid-price insert outperformed the expensive one in pull-out tests. Surprisingly, the cheapest inserts were actually far worse at pull-out resistance than printing undersized holes and threading an M3 screw directly into the plastic.

[Stefan] also looked at torque resistance, and found no substantial difference between the three insert types. Indeed, none of the inserts proved to be the weak point, as the failure mode of all the torque tests was the M3 bolt itself. This didn’t hold with the bolt threaded directly into the plastic, of course; any insert is better than none for torque resistance.

We enjoyed seeing [Stefan]’s tests, and appreciate the data that can help us be informed consumers. [John] over at Project Farm does similar head-to-head tests, like this test of different epoxy adhesives.

Continue reading “Are You Getting Your Money’s Worth From Threaded Inserts?” →

Stackable Open Source 3D Printer Enclosure

December 11, 2019 by Tom Nardi 20 Comments

One of the unfortunate realities of desktop FDM 3D printing is that environmental factors such as ambient temperature and humidity can have a big impact on your results. Even with the exact same settings, a part that printed beautifully in the summer can warp right off the bed during the winter months. The solution is a temperature-controlled enclosure, but that can be a daunting project without some guidance. Luckily, [Jay Doscher] has spent the last few months designing a very impressive enclosure that he’s released to the community as open source.

While we’ve seen no shortage of DIY printer enclosures over the years, they tend to be fairly lightweight. But that’s not the case here. Obviously not wanting to leave anything to chance, [Jay] designed this enclosure with 2020 extrusion and aluminum side panels. You could probably sit on the thing with no ill-effects, which is good, since he also designed the enclosure to be stackable should your print farm need to expand vertically.

Of course, there’s more to this enclosure than just an aluminum box. It’s packed with features like an integrated Raspberry Pi for running Octoprint, internal and external environmental monitoring with the Adafruit SHT31-D, and a Logitech Brio 4K video camera to watch the action. While not currently implemented, [Jay] says he’s also working on an internal fire suppression system and a fan controller system which will circulate air inside the enclosure should things get a little too toasty.

The enclosure has been designed around the ever-popular Prusa i3 MK3/S, even going so far as to relocate the printer’s display to the outside so you don’t have to open the door to fiddle with the settings. But adapting it to whatever rig you happen to be running shouldn’t be a problem. Though admittedly, perhaps not as easy as adjusting an enclosure made out of metal shelving.

Continue reading “Stackable Open Source 3D Printer Enclosure” →