[Punamenon2] wanted a soldering station with integrated helping hands. He couldn’t find one, but he decided it would be a good 3D printed project. In all fairness, this is really 3D printing integrating several off-the-shelf components including a magnifier, a soldering iron holder, a soldering iron cleaner, a couple of “octopus” tripods, and some alligator clips. Total cost? Less than $30.
In addition to holding the Frankenstein monster together, the 3D printed structure also provides a storage tray with special sloped edges to make removing small screws easier.
The project seeks to exploit the traditional symbols of “male” and “female” – the human figures wearing pants or a dress – by creating a sign that switches between the two every 15 seconds. This is likely to initially confuse – one might imagine the bathroom is actually changing its gender designation rapidly, forcing users to complete their business in an incredibly short timeframe. However, the message behind the project is to highlight the absurdity of defining gender by pants, colours, or indeed in a binary nature at all. [Robb] also helpfully points out that all humans have to pass waste, regardless of gender.
The sign is built with 3D-printed components, using a crank mechanism to actuate the moving parts. The mechanism is designed to give equal time to the pants and dress configurations. [Robb] shares the important details necessary to replicate the build, such as how to assemble the metal crank pin insert with a paperclip and a lighter. It’s particularly tidy the way the mechanism is integrated into the parts themselves. In true hacker style, the motor is a standard microwave oven turntable motor, which can be harvested easily from a junk appliance and can be plugged straight into mains power to operate, if you know what you’re doing. If you don’t, check out our primer on the topic.
Overall, the project is a great use of hacker techniques, like 3D printing and harvesting parts, to make a statement and start a conversation, while being fun, to boot. We’ve also seen some of [Robb]’s work before, like this giant hamster wheel for people. Video after the break.
Since the first desktop 3D printers, people have been trying to figure out a way to manage desktop 3D printers and turn them into tiny little automated factories. One of the first efforts was a conveyor belt build plate that was successfully used by MakerBot until it wasn’t anymore. Octoprint has been a boon for anyone who wants to manage a few printers, but that’s only half the solution.
For his Hackaday Prize entry, [Mike] has come up with a solution that turns a desktop 3D printer into a completely automated factory. Not only does this project take care of removing the part from the bed when the print is done, it also manages a web-based print queue. It is the simplest way to manage a printer we’ve ever seen, and it’s a great entry for the Hackaday Prize.
First up, the software stack. [Mike] has developed a web-based queue and slicing software that ingests 3D models and spits out Gcode to a printer. This, really, is nothing new. Octoprint does it, Astroprint does it, and even a few 3D printers have this capability. This is only one part of the project though, although it is geared more as a maker space management software than simply a dedicated 3D printer controller.
You can’t have an automated mini factory without an automated build plate, though, and here [Mike] has come up with something really great. His solution for dispensing prints after they’re completed is brilliant in its simplicity. All you need to do is drop the floor out from underneath the print. [Mike]’s solution is a trap door print bed. At the beginning of the print, an inkjet printer spits out a piece of paper, with a few lines of text, onto the print bed. When the print is finished, a stepper motor unwinds a cable, and a trap door opens up underneath the print. The part drops into a bin, the door closes, and the next print is loaded up in the queue. It’s brilliantly simple.
You can check out [Mike]’s demo of this system after the break. It’s awesome and so sublimely simple we’re shocked no one has thought of this before.
When the Monoprice MP Select Mini 3D printer was released last year, it was a game changer. This was a printer for $200, yes, but it also held a not-so-obvious secret: a 3D printer controller board no one had ever seen before powered by a 32-bit ARM microcontroller with an ESP8266 handling the UI. This is a game-changing set of electronics in the world of 3D printing, and now, finally, someone is reverse engineering it.
[Robin] began the reverse engineering by attaching the lead of an oscilloscope to the serial line between the main controller and display controller. The baud rate is weird (500 kHz), but apart from that, the commands readily appear in human-parsable text. There is a web server built into the MP Mini printer, and after inspecting the web page that’s served up from this printer, [Robin] found it was possible to send G-code directly from the controller board, get a list of files on the SD card, and do everything you would want to do with a 3D printer.
After deconstructing the circuit on the display board, [Robin] found exactly what you would expect from such a simple board: an SPI display driven by an ESP, and a big flash chip sitting off to the side. [Robin] found the the model of the display, and quickly built a project on Platform.io to draw text to the LCD. This isn’t the end of the project – there’s still a lot that must be done before this printer is squirting out parts with custom firmware.
While this isn’t a hack of the driver board inside the MP Mini, that’s not really a problem. The motor driver board in this printer doesn’t really need any changes, and was already ahead of its time when this printer was released last year. As with most things, the UI is the weak point, and upgrading the firmware and built-in web server for this printer is the best way forward.
[Robin] put together a truly phenomenal video of how he reverse engineered this display controller. You can check that out below.
Let’s get something straight right up front: this isn’t much of an electronics project. But it is a very artistic 3D printing project that contains some electronics. [Sjowett] used an off-the-shelf class D amplifier with BlueTooth input to create a simple BlueTooth speaker with a subwoofer. As you can see from the pictures, woofer is exactly the term to use, too.
The clever mechanical design uses 3D printing and common metric PVC pipe. That’s a great technique and resulted in a very clean and professional-looking build. If you don’t have easy access to metric pipe, you could print the pipes, but it will take longer and might not look quite as good.
Much fuss has been made over the strength of 3D printed parts. These parts are obviously stronger in one direction than another, and post processing can increase that strength. What we’re lacking is real data. Luckily, [Justin Lam] has just the thing for us: he’s tested annealed printed plastics, and the results are encouraging.
The current research of annealing 3D printed parts is a lot like metallurgy. If you put a printed part under low heat — below the plastic’s glass transition temperature — larger crystals of plastic are formed. This research is direct from the Society of Plastics Engineers, and we’re assuming they know more about material science than your average joe. These findings measured the crystallinity of a sample in relation to both heat and time, and the results were promising. Plastic parts annealed at a lower temperature can attain the same crystallinity, and therefore the same strength, if they’re annealed for a longer time. The solution is simple: low and slow is the best way to do this, which sounds a lot like sous vide.
A while back, [Justin] built a sous vide controller for the latest cooking fad. The idea behind a sous vide controller is to heat food in a water bath at a lower temperature, but for a longer time. The result here is the most tender steaks you’ll ever have, and also stronger 3D printed parts. In his test, [Justin] printed several rectangular samples of PLA, set the temperature to 70°C, and walked away for a few hours. The samples annealed in the water bath were either cooled quickly or slowly. The test protocol also included measuring the strength in relation to layer height. The test jig consisted of a bathroom scale, a drill press, and a slot head screwdriver bit.
Although the test protocol is slightly questionable, the results are clear: annealing works, but only if the part is printed at a low layer height. However, parts with larger layer heights had a higher maximum stress. Is this helpful for the home prototyper? That depends. The consensus seems to be that if you’re at the mechanical limits of a 3D printed part, you might want to think about more traditional manufacturing. That’s just common sense, but there’s always room to push the envelope of 3D printing.
If you have a few servo motors, an Arduino, and a Bluetooth module, you could make Biped Bob as a weekend project. [B. Aswinth Raj] used a 3D printer, but he also points out that you could have the parts printed by a service or just cut them out of cardboard. They aren’t that complex.
Each of Bob’s legs has two servo motors: one for the hip and one for the ankle. Of course, the real work is in the software, and the post breaks it down piece-by-piece. In addition to the Arduino code, there’s an Android app written using Processing. You can build it yourself, or download the APK. The robot connects to the phone via BlueTooth and provides a simple user interface to do a few different walking gaits and dances. You can see a few videos of Biped Bob in action, below.
This wouldn’t be a bad starter project for a young person or anyone getting started with robotics, especially if you have a 3D printer. However, it is fairly limited since there are no sensors. Then again, that could be version two, if you were feeling adventurous.
We have mixed feelings about the BlueTooth control. BlueTooth modules are cheap and readily available, but so are ESP8266s. It probably would not be very difficult to put Bob on WiFi and let him serve his own control page to any web browser.