Control boards for 3D printers are a dime a dozen on the usual online marketplaces, and you usually get what you pay for. These boards can burn down your house thanks to a few terrible design choices. [Scott Rider] aka [Crow] took a look at the popular Melzi board, and what he found was horrifying. These boards overheat right at the connector for the heated bed, but the good news is these problems are easily fixed.
The Melzi board has a few problems with its PCB design. The first and most glaring issue is the use of thermals on the pads for the heated bed connector. In low-power applications, thermals — the method of not connecting the entire top or bottom layer to a hole or pad — are a great idea. It makes it easier to solder, because heat isn’t transmitted as easily to the entire copper layer. Unfortunately, this means heat isn’t transmitted as easily to the entire copper layer. In high-power applications, like a connection to a heated bed, these thermals can heat up enough to melt a plastic connector. Once that happens, it’s game over.
Other problems were found in the Melzi board, although you wouldn’t know it just by looking at the Eagle file of the PCB. [Scott]’s Chinesium Melzi board used 1-ounce copper, where 2-ounce copper would be more appropriate. The connector, too, should be rated above the design power loading.
[Scott] made a few tweaks to the board and also added a tiny DS1822Z temperature sensor to the high-current area of his version of a Melzi. Imagine that, 3D printer electronics with a temperature sensor. Slowly but surely, the state of 3D printer electronics is clawing its way to the present.
If you’ve played Fallout 4, you’re familiar with the wall-mounted terminals in the game. They’ve got a post-apocalyptic aesthetic and the glowing green screen that calls out to anyone that grew up with computers and hacker movies from the 80s and 90s. Remember the first time you set your command line text to green? Don’t be embarrassed, we were all young once.
[PowerUpProps] liked the Fallout terminal so much they developed a replica. It’s a build that leans heavily on maker standards, a Raspberry Pi and 3D printing form the basis of the terminal. With ready access to such powerful tools, it makes starting such a project much more approachable. The key to the success of this build is the fine attention to detail in the finishing – the paint job looks incredible, and when photographed appropriately, it could be mistaken for
the real thing an in-game screenshot.
An interesting touch is the use of a dark green acrylic window in front of the LCD, which gives the display a tinted hue. We’d like to see this compared with a clear glass window with a classic fishbowl curve to it, combined with greening up in software. The creator readily admits that this looks great at the command line, but is somewhat of a letdown when using the GUI.
Perhaps the only thing the prop build could use is some sort of user interface — the keyboard is only 3D printed and there’s no mouse or other pointing device included. There are some creative solutions to this problem, which we often see in other Fallout projects, like the ever popular Pip-Boy replica builds.
[Thanks to Sjoerd for the tip!]
[Thomas] wanted to try baking some carbon fiber 3D printing filament because the vendor had promised higher strength and rigidity after the parts were annealed in the oven. Being of a scientific mindset, he did some controls and found that annealing parts printed with the carbon fiber-bearing filament didn’t benefit much from the treatment. However, parts printed with standard PLA became quite a bit stronger and more rigid.
The downside? The parts (regardless of material) tend to shrink a bit in the X and Y axis. They also tend to expand in the Z direction. However, the dimension changes were not that much. The test parts shrunk by about 5% and grew by 2%. He didn’t mention if this was repeatable, which is a shame because if it is repeatable, it isn’t a big deal to adjust part dimensions before printing. Of course, if it isn’t repeatable, it will be difficult to get a particular finished size after the annealing process.
Continue reading “Half-Baked Idea: Put Your PLA in the Oven”
There’s something to be said for economies of scale and few things sell more than cell phones. Maybe that’s why [NODE] took inspiration from an iPhone slide out keyboard case to create this Pi Zero W-based portable terminal. This is actually his third iteration, and in the video below he explains why he has built the new version.
By housing the custom bits in a 3D-printed frame that is size compatible with the iPhone, [NODE] manages to leverage the slick slide out keyboard cases available for the phone. The iPhone in question is an older iPhone 5, so the cases are inexpensive, compared to the latest generation. On the other hand, the iPhone 5 is recent enough that it shouldn’t be hard to find a compatible case.
The circuitry itself is pretty straightforward: a battery, a charge controller, and an LCD display. The only complaint we could see was the lack of a control key on the keyboard.
Continue reading “Pi Zero W Impersonates iPhone, Becomes Terminal”
Part smoothing for 3D printed parts, especially parts printed in ABS, has been around for a while. The process of exposing an ABS part to acetone vapor turns even low-resolution prints into smooth, glossy 3D renderings that are stronger than ever. The latest improvement in part smoothing for 3D printed parts is now here: use a brush. Published in Nature‘s Scientific Reports, researchers at Waseda University have improved the ABS + acetone part smoothing process with a brush.
According to the authors of the paper, traditional filament-based printing with ABS has its drawbacks. The grooves formed by each layer forms a porous surface with a poor appearance and low rigidity. This can be fixed by exposing an ABS part to acetone vapor, a process we’ve seen about a million times before. The acetone vapor smoothing process is indiscriminate, though; it smooths and over-smooths everything, and the process involves possible explosions.
The researcher’s solution is a felt tip pen-like device that selectively applies acetone to a 3D printed part. Compared to the print over-smoothed in a vat of acetone vapor, more detail is retained. Also, there’s a ready market for felt tip pens and there isn’t one for crock pots able to contain explosive vapor. This is, therefore, research that can be easily commercialized.
There are many things people do with spare rooms. Some make guest rooms, others make baby rooms, while a few even make craft rooms. What do hackers do with spare rooms? Turn them into giant 3D printers of course. [Torbjørn Ludvigsen] is a physics major out of Umea University in Sweden, and built the Hangprinter for only $250 in parts. It follows the RepRap tradition of being completely open source and made mostly from parts that it can print.
The printer is fully functional, proven by printing a five-foot tall model of the Tower of Babel. [Torbjorn] hopes to improve the printer to allow it to print pieces of furniture and other larger household items.
[Torbjorn] hopes that 3D printing will not go down the same road that 2D printing went, where the printers are designed to break after so many prints. Open source is the key to stopping such machines from getting out there.
Thanks to [Jeremy Southard] for the tip!
Continue reading “Hanging 3D Printer Uses Entire Room As Print Bed”
We’ve had our eye on [Greg Zumwalt]. He’s been working on some very clever 3D-printed mechanisms and his latest prototype is an air engine for a toy car. You can supply the air for the single cylinder with a compressor, or by blowing into it, but attaching an inflated balloon makes the system self-contained.
Last week we saw the prototype of the engine by itself, and wondered if this had enough power to drive a little train engine. We were almost right as here it is powering the front wheels of a little car.
This isn’t [Greg’s] first rodeo. He’s been working on self-contained locomotion for a while now. Shown here is his spring-driven car which you pull backwards to load the spring. It’s a common feature in toys, and very neat to see with the included 3D-printed spring hidden inside of the widest gear.
That print looks spectacular, but the balloon-powered prototype tickles our fancy quite a bit more. Make sure you have your sound on when you watch the video after the break. It’s the chuga-chuga that puts this one over the top. [Greg] hasn’t yet posted files so you can print your own (it’s still a prototype) but browse the rest of his designs as you wait — they’re numerous and will bring an even bigger smile to your face. Remember that domino-laying LEGO bot [Matthias Wandel] built a few years back? [Greg] has a printable model for it!
Continue reading “Toy Car Pumps the Wheels with Balloon Power”