Fusing Plastic Sheets With A 3D Printer (Sort Of)

May 14, 2020 by Tom Nardi 17 Comments

If you want to experiment with pneumatic devices, you’ll likely find yourself in need of custom inflatable bladders eventually. These can be made in arbitrary 2D shapes by using a soldering iron to fuse the edges of two plastic sheets together, but it’s obviously a pretty tedious and finicky process. Now, if only there was some widely available machine that had the ability to accurately apply heat and pressure over a large surface…

Realizing his 3D printer had all the makings of an ideal bladder fusing machine, [Koppany Horvath] recently performed some fascinating experiments to test this concept out in the real-world. Ultimately he considers the attempt to be a failure, but we think he might be being a bit too hard on himself. While he didn’t get the sheets to fuse hard enough to resist being pulled apart by hand, we think he’s definitely on the right track and would love to see more research into this approach.

For these early tests, [Koppany] wrapped the hotend of his Monoprice Maker Select Plus with some aluminum foil, and covered the bed with a piece of cardboard. Stretched over this were two sheets of plastic, approximately 0.5 mil in thickness. Specifically, he used pieces cut from the bags that his favorite sandwiches come in; but we imagine you could swap it out for whatever bag your takeout of choice is conveyed in, assuming it’s of a similar thickness anyway.

There were problems getting the plastic pulled tight enough, but that was mostly solved with the strategic placement of binder clips and a cardboard frame. Once everything was in place, [Koppany] wrote a Python script that commanded the printer to drag the hotend over the plastic at various speeds while simultaneously adjusting the temperature. The goal was to identify the precise combination of these variables that would fuse the sheets of plastic together without damaging them.

In the end, his biggest takeaway (no pun intended) was that the plastic he was using probably isn’t the ideal material for this kind of process. While he got some decent seams at around 180 °C , the thin plastic had a strong tendency towards bunching up. Though he also thinks that a convex brass probe inserted into the hotend could help, as it would smooth the plastic while applying heat.

We’ve already seen some very promising results when using LDPE film in a CO2 laser cutter, but if a entry-level 3D printer could be modified to produce similar results, it could be a real game changer for folks experimenting with soft robotics.

3D Printed Train Set Aims For Speed

May 12, 2020 by Lewin Day 32 Comments

For most involved in the hobby, model trains involve buying track from off-the-shelf suppliers, and lots of delicate painting and finishing. Conversely, [Ivan] just wanted to make something fast and fun, busting out the 3D printer in due course.

While the title of “World’s fastest toy train” is somewhat dubious, the build has its value as an interesting way of doing things. The train is 3D printed, with pressed-in ball bearings and metal shafts for the bogies. Differing from usual practice, this train carries its power supply on board, in the form of a LiPo battery. It’s hooked up to a brushless motor and controlled by a standard RC car setup.

The track is an impressive structure, consisting of 3D printed rails and supports. These are assembled and then screwed down to plywood baseplates, which are hot glued to the flat concrete floor of [Ivan]’s workshop. Strings were used to align everything as straight and true as possible. The track features a steep banking which helps with cornering. However, the straights remain banked in an effort to avoid the complex modelling of a transition. This leads to some derailments at higher speeds on the flat sections.

While it’s not yet perfect, [Ivan] has done a great job of demonstrating a quick and easy way to build a model railway out of almost entirely 3D printed components. We can’t wait to see improvements to the rails and railcars, and hope to see speeds increase significantly in future tests. 3D printing tends to bring some interesting results to bear on the model train world, such as this vertical hanging setup. Video after the break.

Continue reading “3D Printed Train Set Aims For Speed” →

Combine Broken Drone Propellers For A Second Spin

May 6, 2020 by Danie Conradie 8 Comments

If you’ve ever flown or watched anyone fly a racing drone for any length of time, you know that crashes are just part of the game and propellers are consumables. [Adam] knows this all to well, decided to experiment with combining multiple broken propellers into one with a 3D printed hub.

A damaged propeller will often have one blade with no damage, still attached to the hub. [Adam] trimmed the damaged parts of a few broken props, and set about designing a 3D printed hub to attach the loose blades together. The hubs were designed let the individual blades to move, and folding out as the motors spin up, similar to the props on many photography drones.

Once [Adam] had the fit of the hubs dialed in, he mounted a motor on a piece of wood and put the reborn propellers through their paces. A few hubs failed in the process, which allowed [Adam] to identify weak points and optimise the design. This sort of rapid testing is what 3D printing truly excels at, allowing test multiple designs quickly instead of spending hours in CAD trying to foresee all the possible problems.

He then built a test drone from parts he had lying around and proceeded with careful flight testing. The hubs were thicker than standard propellers so it limited [Adams] motor choices to ones with longer shafts. Flight testing went surprisingly well, with a hub only failing after [Adam] changed the battery from a 3 cell to a 4 cell and started with some aerobatics. Although this shows that the new props are not suitable for the high forces from racing or aerobatics/freestyle flying, they could probably work quite well for smoother cruising flights. The hubs could also be improved by adding steel pins into the 3D printed shafts, and some carefully balancing the assembled props.

Continue reading “Combine Broken Drone Propellers For A Second Spin” →

An All Lead Screw 3D Printer You Can Build Yourself

April 30, 2020 by Jenny List 35 Comments

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.

3D Printering: Will A Resin Printer Retire Your Filament-based One?

April 30, 2020 by Donald Papp 25 Comments

Adding a resin printer to one’s workbench has never looked so attractive, nor been so affordable. Complex shapes with effortlessly great detail and surface finish? Yes, please! Well, photos make the results look effortless, anyway. Since filament-based printers using fused deposition modeling (FDM) get solid “could be better” ratings when it comes to surface finish and small detail resolution, will a trusty FDM printer end up retired if one buys a resin printer?

The short answer is this: for users who already use FDM, a resin-based stereolithography (SLA) printer is not likely to take over. What is more likely to happen is that the filament printer continues to do the same jobs it is good at, while the resin printer opens some wonderful new doors. This is partly because those great SLA prints will come at a cost that may not always justify the extra work.

Let’s go through what makes SLA good, what it needs in return, and how it does and doesn’t fit in with FDM.

Continue reading “3D Printering: Will A Resin Printer Retire Your Filament-based One?” →

Signal The End Of A Print With MIDI Of Your Choice

April 25, 2020 by Danie Conradie 6 Comments

The end of every 3D print should be a triumphant moment, and deserves a theme song. [FuseBox2R] decided to make it a reality, and wrote tool for converting MIDI tracks to G-code that uses the buzzer on your 3D printer.

The tool is up on GitHub, and uses the M300 speaker command that is available in Marlin and some other 3D printer firmware packages. It takes the form of a static HTML page with in-line JavaScript that converts a midi track to series of speaker commands with the appropriate frequency and duration parameters, using the Tone.js framework. Simply add to your slicer G-code to add a bit of spice to your prints. You can also build a MIDI jukebox using the RAMPS board and LCD you probably have gathering dust somewhere. See the video after the break for a demonstration, including a rendition of the DOOM theme song, and off course Mario Bros.

For more quarantine projects, you can also play MIDI using the stepper motors on your printer, or build a day clock if time is becoming too much of a blur.

Continue reading “Signal The End Of A Print With MIDI Of Your Choice” →

Queue Up Your Tracks With A Well Placed Hexagon

April 24, 2020 by Tom Nardi 11 Comments

Besides a few stalwart holdouts, most of us have have switched over listening to music in digital form, often via an online stream. As long as no data caps stand in your way, it’s a quick and easy way to listen to your favorite artists or discover new ones. But there’s something visceral about act of loading a piece of physical media into a player that can’t be replicated by just clicking or tapping on a screen.

Which is why [InfiniteVideo] put together this RFID playlist launcher peripheral. There’s an important distinction to be made here, as this device isn’t actually playing or even storing audio. A nearby Raspberry running Volumio handles the actual playback. This device is just an RFID reader with some clever tokens that the listener can use to select their favorite artists and albums with physical tokens. It’s certainly not a new concept, but we think the nuances of this particular build warrant a closer look.

The “player” consists of a ESP8266 with a MFRC522 RFID reader wired directly to the GPIO pins. The pair are housed in a rather large 3D printed enclosure, which at first might seem a bit excessive. But it turns out that [InfiniteVideo] is actually trying to replicate a crowd sourced project called Qleek which is based around a similarly chunky reader.

Likewise, the hexagon tiles are also lifted from the Qleek concept. But rather than being made out of wood as in the original, [InfiniteVideo] is printing those as well. Halfway during the process, the print is paused and an RFID sticker is placed in the middle of the hexagon. Once resumed, the RFID tag becomes permanently embedded in the tile with no visible seams to reveal how the trick was pulled off. With the addition of a suitable label, each printed hexagon gets associated with the desired album or artist in software.

This project is notable for its convenience and visual flair, but using RFID tags for media identification can also be a practical choice. It can be used as an assistive technology, or as a way for young children to easily interact with devices.