Hackaday editors Mike Szczys and Elliot Williams march to the beat of the hardware hacking drum as they recount the greatest hacks to hit the ‘net this week. First up: Casio stepped in it with a spurious DMCA takedown notice. There’s a finite matrix of resistors that form a glorious clock now on display at CERN. Will a patio paver solve your 3D printer noise problems? And if you ever build with copper clad, you can’t miss this speedrun of priceless prototyping protips.
There was a time when the curious hardware hacker had to build their own 3D printer, because commercial models were so expensive as to be unaffordable except by well-funded institutions. We’re fortunate then to live in an era in which a good quality off-the-shelf machine can be had without breaking the bank, but that is not to say that home-made 3D printers are a thing of the past. Instead the community of rapid prototyping experimenters continue to push the boundaries of the art, and from that we all benefit. An example comes from [Morgan Lowe], whose 3DLS lead screw driven 3D printer joins the freely downloadable designs to be found on Thingiverse.
If at first sight you think it looks a little familiar, you are correct, as it takes its frame design from the popular AM8 metal frame upgrade for the Anet A8 off-the-shelf printer. It draws heavily from other A8 upgrades, and brings in some parts such as the extruder and bed from the Creality Ender3. This is the beauty of incremental open source, and the result is a belt-free printer that does a decent-looking Benchy on the bench, and as a party piece manages to print a slightly more hairy little plastic boat when suspended at 45 degrees by a rope from the ceiling.
When dipping a toe into the world of home made 3D printers it’s interesting to take a look into some of the earlier Hackaday RepRap posts, and see how far we’ve come.
Flexible steel sheets as the foundation for build platforms are used to great advantage in FDM 3D printers. These coated sheets are held flat by magnets during printing, and after printing is done the sheet (with print attached) can be removed and flexed to pop the prints free. This got [Jan Mrázek] thinking. He was pretty sure the concept could extend to the build platform on his Elegoo Mars resin printer. With a flexible build platform, troublesome prints could be more easily removed, so he non-destructively modified his printer to have a similar system. [Jan] is clear that this is only a proof of concept, but the test results were good! He printed several jobs that were known to be trouble, and they were all a piece of cake to remove.
[Jan]’s mod consists of a 3D printed, two-piece unit that encapsulates the normal build platform and contains a few strong magnets. A thin sheet of steel sticks flat to this new piece, held in place by the magnets within, and becomes the new build platform. After a print is done, the sheet is removed and [Jan] reports that its flexibility is a big help in removing otherwise troublesome prints, such as the 3D printed solder stencil we covered recently.
[Jan] provides his CAD model but doesn’t really recommend using it for anything other than development work. Results were promising, but there are a number of drawbacks to the prototype. For one thing, it makes the build platform thicker and the Z-axis limit switch needs to be physically lowered in order to zero the unit. Also, the thicker build platform means the volume of resin the build tank can hold is reduced. Still, the idea clearly has merit and shows there absolutely is value in hardware having a hackable design.
We see a lot of 3D printers here at Hackaday, but as over the years the 3D printer has moved from being an exciting item in its own right to being an everyday tool, it’s increasingly rare for us to feature a build of one as a project. It’s especially rare for us to see a 3D printer that isn’t a variation of either an XYZ Cartesian design or a delta printer, but that’s what [bondus] has done with a printer based upon a parallel SCARA mechanism. If SCARA isn’t something you’re familiar with, it’s a design used in the world of industrial robots in which an almost humanoid jointed arm works in two dimensions, with the third being provided by raising or lowering the whole construction. It has the advantage of greater speed than Cartesian designs, at the expense of higher quality joints being required to maintain accuracy of positioning.
This is the second SCARA printer he’s built, and has a sturdy set of aluminium arms and substantial bearings. Drive comes via a pair of belts to some very large pulleys, and calibration is extremely important to ensure that both arms are in exactly the same plane. The curcular bed is on a lead screw that provides the Z axis.
The results are certainly impressive, both is speed and in print quality. We’ve placed a video of it in action below the break. Whether or not SCARA printers improve to the point of being ubiquitous isn’t something we can supply an answer to, but we’ve featured a small number of them in the past. Particularly memorable is this one using an industrial robotic arm.
At a recent swap meet, [digitalrice] found what appeared to be a like-new QIDI X-Plus 3D printer. It wasn’t clear what was wrong with it, but considering it retails for $900 USD, he figured the asking price of $150 was worth the gamble. As you might expect, the printer ended up being broken. But armed with experience and a supply of spare parts, he was able to get this orphaned machine back up and running.
The first and most obvious problem was that the printer’s Z axis didn’t work properly. When the printer tried to home the axis, one of the motors made a terrible noise and the coupler appeared to be spinning backwards. From his experience with other printers, [digitalrice] knew that the coupler can slip on the shaft, but that didn’t appear to be the case here. Removing the stepper motor and testing it in isolation from the rest of the machine, he was able to determine it needed replacing.
Unfortunately, the spare steppers he had weren’t actually the right size. Rather than waiting around for the proper one to come in the mail, he took an angle grinder to the stepper’s shaft and cut off the 5 mm needed to make it fit, followed by a few passes with a file to smooth out any burrs. We’re not sure we’d recommend this method of adjustment under normal circumstances, but we can’t argue with the results.
The replaced Z motor got the printer moving, but [digitalrice] wasn’t out of the woods yet. At this point, he noticed that the hotend was hopelessly clogged. Again relying on his previous experience, he was able to disassemble the extruder assembly and free the blob of misshapen PLA, leading to test prints which looked very good.
But success was short lived. After swapping to a different filament, he found it had clogged again. While clearing this second jam, he realized that the printer’s hotend seemed to have a design flaw. The PTFE tube, which is used to guide the filament down into the hotend, didn’t extend far enough out. Right where the tube ended, the filament was getting soft and jamming up the works. With a spare piece of PTFE tube and some manual reshaping, he was able to fashion a new lining which would prevent the filament from softening in this key area; resulting in a more reliable hotend than the printer had originally.
It’s great to see this printer repaired to working condition, especially since it looks like [digitalrice] was able to fix a core design flaw. But a broken 3D printer can also serve as the base for a number of other interesting projects, should you find yourself in a similar situation. For example, replacing the extruder assembly with a digital microscope can yield some very impressive results.
A few years ago, [Wayne] managed to blow out the main board of his Flashforge Finder attempting to change the fan. But the death of one tool ended up being the birth of another, as he ended up using its mechanical components and a Raspberry Pi to create an impressive scanning microscope.
As you might have guessed from the name, the idea here is to scan across the object with a digital microscope to create an enlarged image of the entire thing. This requires some very precise control over the microscope, which just so happens to be exactly what 3D printers are good at. All [Wayne] had to do was remove the hotend, and print some adapter pieces which let him mount a USB microscope in its place.
The rest is in the software. The Raspberry Pi directs the stepper motors to move the camera across the object to be scanned in the X and Y dimensions, collecting thousands of individual images along the way. Since the focus of the microscope is fixed and there might be height variations in the object, the Z stage is then lifted up a few microns and the scan is done again. Once the software has collected tens of thousands of images in this manner, it sorts through them to find the ones that are in focus and stitch them all together.
The process is slow, and [Wayne] admits its not the most efficient approach to the problem. But judging by the sample images on the Hackaday.io page, we’d say it gets the job done. In fact, looking at these high resolution scans of 3D objects has us wondering if we might need a similar gadget here at the Hackaday Command Bunker.
Human brains are wired for music. Scientists think the oldest musical instruments were flutes that date back somewhere between 67,000 and 37,000 years ago. We assume though that people were banging on wood or their thighs, or knocking two rocks together long before that. Almost anything can be a musical instrument. A case in point: [elifer5000] walked into a room containing a lot of running 3D printers, and thought it seemed musical. Next thing you know, he harnessed 3D printers as a MIDI instrument.
At a hackathon, he found some software that converts a MIDI file to GCode. The only problem is a common printer has three axes and, therefore, can only produce (at most) three notes at once. The obvious answer to this problem is to use more printers, and that’s what he did, as you can see below.