Microwave oven design and manufacturing have been optimized to the point where the once-expensive appliances are now nearly disposable. Despite the economics, though, some people can’t resist fixing stuff, especially when you get a chance to do it in style. Thus we present this microwave repair with its wholly unnecessary yet fabulous adornments.

The beginning of the end for [dekuNukem]’s dirt cheap second-hand microwave started where many of the appliances begin to fail first — the membrane keyboard. Unable to press the buttons reliably anymore, [dekuNukem] worked out the original keypad’s matrix wiring arrangement and whipped up a little keypad from some pushbutton switches and a scrap of perfboard. Wired into the main PCB, it was an effective and cheap solution, if a bit on the artless side.

To perk things up a bit, [dekuNukem] turned to duckyPad, a hot-swappable macropad with mechanical switches and, of course, RGB LEDs. Things got interesting from here; since duckyPad outputs serial data, an adapater was needed inside the microwave. An STM32 microcontroller and a pair of ADG714 analog switches did the trick, with power pulled from the original PCB.

The finished repair is pretty flashy, and [dekuNukem] now has the only microwave in the world with a clicky keypad. And what’s more, it works.

source https://hackaday.com/2020/11/15/a-microwave-repair-even-mechanical-keyboard-fans-will-love/

These days, a classic Jack O’ Lantern just doesn’t cut the mustard. Kids are expecting to be scared by high-quality animatronics at a minimum. This haunting work by [Zero To Infinity] might just do the trick.

A real pumpkin is pressed into service in this build, with the usual threatening grin and candlelit interior. However, where it differs is in its single, animated eye. The eye itself is constructed of a pingpong ball, drawn upon with markers for a creepy bloodshot look. A pair of servos allow the eye to twitch and roll, under the command of an Arduino Nano. For further interactivity, an ultrasonic sensor is used to only trigger the pumpkin when it senses a person approaching.

It’s a fun holiday build that also serves as a great primer on how to work with servos and microcontrollers. We can imagine a more advanced setup using more sensors and pumpkins to train multiple eyes on the unsuspecting visitor. If that’s not scary enough, perhaps just make your pumpkins breathe fire instead. Video after the break.

source https://hackaday.com/2020/11/15/halloween-pumpkin-scares-with-an-evil-eye/

[DIY3DTech] likes using his Ortur laser cutter for balsa wood and decided to add an air assist system to it. Some people told him it wasn’t worth the trouble, so in the video below, he compares the results of cutting both with and without the air assist.

The air assist helped clear the cut parts and reduced charring in the wood. The air system clears residue and fumes that can reduce the effectiveness of the laser. It can also reduce the risk of the workpiece catching on fire.

In addition, the video shows the results of cutting wood using different speeds and number of passes. So the holes marked 5/10, for example, are cut at 5mm/second and ten passes.

Although air assist might help if you are engraving, the real benefit, according to the video, is when you are trying to do cuts. However, removing the fumes is probably a good idea even when engraving.

The video doesn’t go into much detail about the air system, but there are links in the video description to pages that have more information about how to add something like this to your laser cutting setup. There’s also a more recent video specifically about how the air assist system works.

If you need more on laser cutter basics, we read a great post about it last year. Like 3D printers, it used to be fashionable to build your own cutter, but now it is cheap enough to buy one if you’d rather not mess with it.

source https://hackaday.com/2020/11/15/cutting-balsa-wood-with-air-oh-and-a-laser/

Old-school rail monitoring systems had amazing displays of stations and tracks covered in flashing lights that tracked the progress of trains along a route. While it’s unlikely you’ll fit such big iron from the mid-20th century in your home, you can get a similar aesthetic with [Kothe’s] interactive subway information display.

The display relies on an Arduino Mega 2560 Pro Mini as the brains of the operation. It drives strings of WS2812B LEDs which correspond to stations along the various metro lines in the area. Additionally, the microcontroller drives a 4.3″ Nextion LCD display. The Nextion displays have the benefit of acting as a self-contained human machine interface, running their own controller on board. This means the Arduino doesn’t have to spend cycles driving the display, and the Nextion hardware comes with a useful software package for quickly and easily designing GUI interfaces. For further feedback, a DFPlayer MP3 module is used to allow the system to playback prerecorded voice samples that provide information on the rail system. The attractive front panel is made with lasercut acrylic and a color printed acetate sheet.

It’s a build that bears striking similarity to real rail information systems fielded by railways around the world. We can imagine such a device being particularly useful in a backpacker’s hostel or university dorm to help those new to town find their way around. If you prefer a more stripped-back aesthetic, we’ve seen a barebones PCB build done as well. Video after the break.

source https://hackaday.com/2020/11/15/interactive-subway-map-talks-you-through-the-route/

With electric vehicles such as the Tesla or the Leaf being all the rage and joined by fresh competitors seemingly every week, it seems the world is going crazy for the electric motor over their internal combustion engines. There’s another sector to electric traction that rarely hits the headlines though, that of converting existing IC cars to EVs by retrofitting a motor. The engineering involved can be considerable and differs for every car, so we’re interested to see an offering for the classic Mini from the British company Swindon Powertrain that may be the first of many affordable pre-engineered conversion kits for popular models.

The kit takes their HPD crate EV motor that we covered earlier in the year, and mates it with a Mini front subframe. Brackets and CV joints engineered for the kit to drop straight into the Mini. The differential appears to be offset to the right rather than the central position of the original so we’re curious about the claim of using the Mini’s own driveshafts, but that’s hardly an issue that should tax anyone prepared to take on such a task. They can also supply all the rest of the parts for a turnkey conversion, making for what will probably be one of the most fun-to-drive EVs possible.

The classic Mini is now a sought-after machine long past its days of being dirt-cheap old-wreck motoring for the masses, so the price of the kit should be viewed in the light of a good example now costing more than some new cars. We expect this kit to have most appeal in the professional and semi-professional market rather than the budget end of home conversions, but it’s still noteworthy because it is a likely sign of what is to come. We look forward to pre-engineered subframes becoming a staple of EV conversions at all levels. The same has happened with other popular engine upgrades, and no doubt some conversions featuring them will make their way to the pages of Hackaday.

We like the idea of conversions forming part of the path to EV adoption, as we’ve remarked before.

source https://hackaday.com/2020/11/15/an-ev-conversion-engineered-as-a-drop-in-replacement/

With electric vehicles such as the Tesla or the Leaf being all the rage and joined by fresh competitors seemingly every week, it seems the world is going crazy for the electric motor over their internal combustion engines. There’s another sector to electric traction that rarely hits the headlines though, that of converting existing IC cars to EVs by retrofitting a motor. The engineering involved can be considerable and differs for every car, so we’re interested to see an offering for the classic Mini from the British company Swindon Powertrain that may be the first of many affordable pre-engineered conversion kits for popular models.

The kit takes their HPD crate EV motor that we covered earlier in the year, and mates it with a Mini front subframe. Brackets and CV joints engineered for the kit to drop straight into the Mini. The differential appears to be offset to the right rather than the central position of the original so we’re curious about the claim of using the Mini’s own driveshafts, but that’s hardly an issue that should tax anyone prepared to take on such a task. They can also supply all the rest of the parts for a turnkey conversion, making for what will probably be one of the most fun-to-drive EVs possible.

The classic Mini is now a sought-after machine long past its days of being dirt-cheap old-wreck motoring for the masses, so the price of the kit should be viewed in the light of a good example now costing more than some new cars. We expect this kit to have most appeal in the professional and semi-professional market rather than the budget end of home conversions, but it’s still noteworthy because it is a likely sign of what is to come. We look forward to pre-engineered subframes becoming a staple of EV conversions at all levels. The same has happened with other popular engine upgrades, and no doubt some conversions featuring them will make their way to the pages of Hackaday.

We like the idea of conversions forming part of the path to EV adoption, as we’ve remarked before.

source https://hackaday.com/2020/11/15/an-ev-conversion-engineered-as-a-drop-in-replacement/

With electric vehicles such as the Tesla or the Leaf being all the rage and joined by fresh competitors seemingly every week, it seems the world is going crazy for the electric motor over their internal combustion engines. There’s another sector to electric traction that rarely hits the headlines though, that of converting existing IC cars to EVs by retrofitting a motor. The engineering involved can be considerable and differs for every car, so we’re interested to see an offering for the classic Mini from the British company Swindon Powertrain that may be the first of many affordable pre-engineered conversion kits for popular models.

The kit takes their HPD crate EV motor that we covered earlier in the year, and mates it with a Mini front subframe. Brackets and CV joints engineered for the kit to drop straight into the Mini. The differential appears to be offset to the right rather than the central position of the original so we’re curious about the claim of using the Mini’s own driveshafts, but that’s hardly an issue that should tax anyone prepared to take on such a task. They can also supply all the rest of the parts for a turnkey conversion, making for what will probably be one of the most fun-to-drive EVs possible.

The classic Mini is now a sought-after machine long past its days of being dirt-cheap old-wreck motoring for the masses, so the price of the kit should be viewed in the light of a good example now costing more than some new cars. We expect this kit to have most appeal in the professional and semi-professional market rather than the budget end of home conversions, but it’s still noteworthy because it is a likely sign of what is to come. We look forward to pre-engineered subframes becoming a staple of EV conversions at all levels. The same has happened with other popular engine upgrades, and no doubt some conversions featuring them will make their way to the pages of Hackaday.

We like the idea of conversions forming part of the path to EV adoption, as we’ve remarked before.

source https://hackaday.com/2020/11/15/an-ev-conversion-engineered-as-a-drop-in-replacement/

Minigolf is a fun, simple pastime that has the benefit of taking up much less space than the classical game it is inspired by. [gcall1979] had built himself a small game for the lounge room, but found keeping score to be a tedious exercise. Of course, that was nothing that couldn’t be solved with some electronics!

The game consists of a skeeball-type minigolf course, where the score is determined by the hole the player puts the ball through. To track this, each hole is fitted with an IR break-beam sensor that triggers when a ball passes through. Vinyl siding is used to guide the balls going through the holes to ensure the sensor is triggered consistently. The sensors are read by an Arduino Mega, which is also responsible for flashing LEDs and updating the score throughout the game on the included 7-segment displays.

It’s a basic hack, but one that makes the game far more of a self-contained experience. No more fumbling with pencils and paper means it’s easier to focus on dominating the competition on the (miniature) green. Of course, those with dreams of the driving range might consider this recreation of the famous Floating 14th Hole!

source https://hackaday.com/2020/11/14/automatic-scoring-for-skeeball-mini-golf/

There are plenty of small microcontrollers available for all kinds of tasks, each one with its unique set of features and capabilities. However, not all of us want to spend time mucking about in C or assembly to learn the intricacies of each different chip. If you prefer the higher planes of Python instead, it’s not impossible to import Python on even the smallest of microcontrollers thanks to MicroPython, which [Rob] shows us in this project based on the ESP32.

[Rob] has been working on a small robot called Marty which uses an ESP32 as its brain, so the small microcontroller is already tasked with WiFi/Bluetooth communications and driving the motors in the robot. Part of the problem of getting Python to run on a platform like this is that MicroPython is designed to be essentially the only thing running on the device at any one point, but since the ESP32 is more powerful than the minimum requirements for MicroPython he wanted to see if he could run more than just Python code. He eventually settled on a “bottum-up” approach to build a library for the platform, rather than implementing MicroPython directly as a firmware image for the ESP32.

The blog post is an interesting take on running Python code on a small platform, and goes into some details with the shortcomings of MicroPython itself which [Rob] ended up working around for this project. He’s also released the source code for his work on his GitHub page. Of course, for a different approach to running Python and C on the same small processor, there are some libraries that accomplish that as well.

source https://hackaday.com/2020/11/14/micropython-on-microcontrollers/

When looking for the best deal, it pays to shop around. When it comes to chain stores, of course, one expects the price to be the same across their retail network. However, where international companies are concerned, occasionally a better deal is just a border crossing away. To investigate the best possible price on IKEA’s flatpacked goods, [Sn0w5t0rm] whipped up a scirpt to make comparisons easy.

The hack consists of a small piece of Javascript that runs in a browser extension like Greasemonkey (Firefox) or Tampermonkey (Chrome). When visiting an IKEA product page, it shows the price of the same item in the alternative country of your choice. Often, significant savings can be had – the SKOGSTA table is €176 cheaper in the Netherlands compared to Belgium.

While the script does require some customization to suit your location, it could nonetheless save you a bundle on some home furnishings if your live near enough to a border. We’d love to see the concept taken further to tease out best prices in a given region for goods from all stores. Similar techniques can net you cheap airfares, too!

source https://hackaday.com/2020/11/14/a-different-kind-of-ikea-hack-javascript-price-comparison-by-location/

When we think of 3D printed parts for our projects, most of us imagine little bits like brackets and mounting plates. Perhaps the occasional printed project enclosure. But if you’ve got a big custom printer as [Joshendy] does, plus plenty of time, it opens up a whole new world of large scale projects. Take for example the gorgeous RGB LED guitar body he recently completed.

Despite the considerable 300 x 300 mm build area of his custom 3D printer, [Joshendy] still had to design the guitar body in sections that could be bolted together after being printed in ABS. It took around 60 hours to run off all the parts, with the large central section taking the longest to print at 28 hours. With the generous application of heat-set inserts, the assembled guitar should be plenty strong.

While the skeletal plastic body of the guitar is certainly visually interesting in itself, it only makes up for half of the final look. Inside the central cavity, [Joshendy] has embedded two strips of RGB LEDs, a 128×64 OLED screen, and a custom PCB that plays host to a STM32L4 microcontroller the appropriate voltage regulators necessary to run it all on a battery pack.

The board taps into the audio being produced by the guitar and uses a fast Fourier transform (FFT) to get the LEDs reacting to the beat. As demonstrated in the video after the break, you can use the screen to navigate through the different lighting modes in real-time right on the instrument itself.

We covered the equally impressive large-format 3D printer that [Joshendy] used to produce this guitar earlier in the month, and it’s quite exciting to see the sort of things he’s printing on it already. This project has already set the bar very high, and we can’t wait to see what he comes up with next.

source https://hackaday.com/2020/11/14/illuminated-3d-printed-guitar-is-ready-to-rock/

When we think of 3D printed parts for our projects, most of us imagine little bits like brackets and mounting plates. Perhaps the occasional printed project enclosure. But if you’ve got a big custom printer as [Joshendy] does, plus plenty of time, it opens up a whole new world of large scale projects. Take for example the gorgeous RGB LED guitar body he recently completed.

Despite the considerable 300 x 300 mm build area of his custom 3D printer, [Joshendy] still had to design the guitar body in sections that could be bolted together after being printed in ABS. It took around 60 hours to run off all the parts, with the large central section taking the longest to print at 28 hours. With the generous application of heat-set inserts, the assembled guitar should be plenty strong.

While the skeletal plastic body of the guitar is certainly visually interesting in itself, it only makes up for half of the final look. Inside the central cavity, [Joshendy] has embedded two strips of RGB LEDs, a 128×64 OLED screen, and a custom PCB that plays host to a STM32L4 microcontroller the appropriate voltage regulators necessary to run it all on a battery pack.

The board taps into the audio being produced by the guitar and uses a fast Fourier transform (FFT) to get the LEDs reacting to the beat. As demonstrated in the video after the break, you can use the screen to navigate through the different lighting modes in real-time right on the instrument itself.

We covered the equally impressive large-format 3D printer that [Joshendy] used to produce this guitar earlier in the month, and it’s quite exciting to see the sort of things he’s printing on it already. This project has already set the bar very high, and we can’t wait to see what he comes up with next.

source https://hackaday.com/2020/11/14/illuminated-3d-printed-guitar-is-ready-to-rock/

When we think of 3D printed parts for our projects, most of us imagine little bits like brackets and mounting plates. Perhaps the occasional printed project enclosure. But if you’ve got a big custom printer as [Joshendy] does, plus plenty of time, it opens up a whole new world of large scale projects. Take for example the gorgeous RGB LED guitar body he recently completed.

Despite the considerable 300 x 300 mm build area of his custom 3D printer, [Joshendy] still had to design the guitar body in sections that could be bolted together after being printed in ABS. It took around 60 hours to run off all the parts, with the large central section taking the longest to print at 28 hours. With the generous application of heat-set inserts, the assembled guitar should be plenty strong.

While the skeletal plastic body of the guitar is certainly visually interesting in itself, it only makes up for half of the final look. Inside the central cavity, [Joshendy] has embedded two strips of RGB LEDs, a 128×64 OLED screen, and a custom PCB that plays host to a STM32L4 microcontroller the appropriate voltage regulators necessary to run it all on a battery pack.

The board taps into the audio being produced by the guitar and uses a fast Fourier transform (FFT) to get the LEDs reacting to the beat. As demonstrated in the video after the break, you can use the screen to navigate through the different lighting modes in real-time right on the instrument itself.

We covered the equally impressive large-format 3D printer that [Joshendy] used to produce this guitar earlier in the month, and it’s quite exciting to see the sort of things he’s printing on it already. This project has already set the bar very high, and we can’t wait to see what he comes up with next.

source https://hackaday.com/2020/11/14/illuminated-3d-printed-guitar-is-ready-to-rock/

Linux finds a lot of uses in computers that aren’t desktops. But there is a problem. What happens if your mission-critical control computer or retail kiosk gets an update and then fails? Happens all the time with Windows and it can happen with Linux, too. The openSUSE project has an answer: MicroOS which bills itself as immutable. Aimed at container deployment, the operating system promises atomic updates with no disk changes during runtime. If an update does break something, the BTRFS file system allows you to roll back to a previous snapshot. [Tyler] installs the OS and gives it a walkthrough in the video below.

As [Tyler] found, there are not many applications installed by default. Instead, you are expected to install flatpaks so the applications live in their own containers, isolated from the operating system and each other.

Of course, this isn’t for everyone. On the other hand, there is something seductive about having a computer that is very reliable even in the face of updates. Of course, you can do snapshots with BTRFS or ZFS anywhere those are supported, but unless you are very careful, you might have problems with dependencies for applications and the wrong update can still ruin your day. The OS supports GNOME or KDE, with system requirements that claim you can run it in 1GB of RAM and 20GB of disk space. We’d imagine you’ll be happier if you have more, of course.

If you are interested in snapshot file systems for the PI, you can play with BTRFS on that platform. We imagine you could develop some super robust system using FUSE, too, if someone hasn’t already done it.

source https://hackaday.com/2020/11/14/microos-is-immutable-linux/

When it rain, it pours. One of the primary support cables holding up the Arecibo Observatory dish in Puerto Rico has just snapped, leaving its already uncertain fate. It had been badly damaged by Hurricane Maria in 2017, and after a few years of fundraising, the repairs were just about to begin on fixing up that damage, when the cable broke. Because the remaining cables are now holding increased weight, humans aren’t allowed to work on the dome until the risk of catastrophic failure has been ruled out — they’re doing inspection by drone.

Arecibo Observatory has had quite a run. It started out life as part of a Cold War era ICBM-tracking radar, which explains why it can transmit as well as receive. And it was the largest transmitting dish the world had. It was used in SETI, provided the first clues of gravitational waves, and found the first repeating fast radio bursts. Its radar capabilities mean that it could be used in asteroid detection. There are a number of reasons, not the least of which its historic import, to keep it running.

So when we ran this story, many commenters, fearing the worst, wrote in with their condolences. But some wrote in with outrage at the possibility that it might not be repaired. The usual suspects popped up: failure to spend enough on science, or on infrastructure. From the sidelines, however, and probably until further structural studies are done, we have no idea how much a repair of Arecibo will cost. After that, we have to decide if it’s worth it.

Per a 2018 grant, the NSF was splitting the $20 M repair and maintenance bill with a consortium led by the University of Central Florida that will administer the site. With further damage, that might be an underestimate, but we don’t know how much of one yet.

When do you decide to pull the plug on something like this? Although the biggest, Arecibo isn’t the only transmitter out there. The next largest transmitters are part of Deep Space Network, though, and are busy keeping touch with spacecraft all around our solar system. For pure receiving, China’s FAST is bigger and better. And certainly, we’ve learned a lot about radio telescopes since Arecibo was designed.

I’m not saying that we won’t shed a tear if Arecibo doesn’t get repaired, but it’s not the case that the NSF’s budget has been hit dramatically, or that they’re unaware of the comparative value of various big-ticket astronomy projects. Without being in their shoes, and having read through the thousands of competing grant proposals, it’s hard to say that the money spent to prop up a 70 year old telescope wouldn’t be better spent on something else.

source https://hackaday.com/2020/11/14/what-is-worth-saving/

[SamsonMarch] designs electronic products by day and — apparently — does it in his spare time, too. His latest is a pair of really cool shades that give him turn-by-turn directions as he walks around town. Unlike some smart glasses, these get around the difficult problem of building a heads-up display by using a very simple interface based on colored LEDs visible to your peripheral vision in the temples of the frames.

The glasses themselves look great; designed in Fusion 360 and cut out of wood, no one would give them a second glance. [Sam] says you could 3D print them, too, but we think the wood looks best even if the stock is a cheap bamboo cutting board. He also cut the lenses out of acrylic.

The slots in the temples are where the action is, though. An iPhone app takes input and talks to Apple services to get directions. A lot of thought went into making the app work even though the phone keeps trying to put it to sleep. Each PCB hosts an RGB LED for indicating left/right turn and destination. They talk to the app using BLE and include accelerometers which put the boards — powered by coin cells — into sleep mode when no movement is detected.

Overall a fun and good looking project. There are even covers to hide the boards during normal use. The files you need to reproduce it are on GitHub. Usually, when we see smart glasses, they have some sort of screen which is harder to do. Of course, it is impossible to avoid comparisons to Google Glass.

View post on imgur.com

source https://hackaday.com/2020/11/14/turn-by-turn-smart-glasses-give-you-direction/

Dremel’s attempt at breaking into the 3D printer market back in 2014 was respectable, if not particularly exciting. Rather than design their own printer, their 3D20 “Idea Builder” was a lightly customized Flashforge Dreamer (itself a Makerbot Replicator clone) with a new warranty and support contract tacked on. It wasn’t necessarily the 3D printer of choice for the hacker and maker crowd, but it was a fairly solid option for folks who wanted a turn-key experience.

[Chris Chimienti] says he got about 1,000 hours of printing out of his 3D20 before it gave up the ghost. Given the age of the machine and its inherent limitations, he decided to use the Dremel’s carcass as the base for a very impressive custom 3D printer with all the modern bells and whistles. He kept the enclosure, rods, bearings, and the stepper motors, but pretty much everything else was tossed out. Some of the replacements are off-the-shelf parts, but it’s the custom designed elements on this build that really help set it apart.

Under the machine, [Chris] has installed a new power supply and a Duet 2 WiFi controller which itself is connected to the new LCD control panel on the front. There’s an external case fan to keep the electronics cool, but otherwise things look a lot neater under the hood than they did originally.

Moving upwards, he’s designed a gorgeous adjustable print bed and a new extruder assembly that cleverly uses RJ45 jacks and Ethernet cables to connect back to the control board. All told, the custom components have taken this once relatively mid-range 3D printer and turned it into something that looks like it wouldn’t be out of place on the International Space Station.

While custom 3D printer builds like this still trickle in from time to time, we’re seeing far fewer now than we did back when machines like the 3D20 hit the market. Most people are more than satisfied with commercial entry-level desktop printers, and aren’t looking for yet another project to tinker with. There’s nothing wrong with that, though we certainly wouldn’t complain if the recent interest into more advanced high-temperature filaments triggered something of a bespoke 3D printer renaissance.

source https://hackaday.com/2020/11/14/dremel-3d20-printer-gets-modern-overhaul/

Dremel’s attempt at breaking into the 3D printer market back in 2014 was respectable, if not particularly exciting. Rather than design their own printer, their 3D20 “Idea Builder” was a lightly customized Flashforge Dreamer (itself a Makerbot Replicator clone) with a new warranty and support contract tacked on. It wasn’t necessarily the 3D printer of choice for the hacker and maker crowd, but it was a fairly solid option for folks who wanted a turn-key experience.

[Chris Chimienti] says he got about 1,000 hours of printing out of his 3D20 before it gave up the ghost. Given the age of the machine and its inherent limitations, he decided to use the Dremel’s carcass as the base for a very impressive custom 3D printer with all the modern bells and whistles. He kept the enclosure, rods, bearings, and the stepper motors, but pretty much everything else was tossed out. Some of the replacements are off-the-shelf parts, but it’s the custom designed elements on this build that really help set it apart.

Under the machine, [Chris] has installed a new power supply and a Duet 2 WiFi controller which itself is connected to the new LCD control panel on the front. There’s an external case fan to keep the electronics cool, but otherwise things look a lot neater under the hood than they did originally.

Moving upwards, he’s designed a gorgeous adjustable print bed and a new extruder assembly that cleverly uses RJ45 jacks and Ethernet cables to connect back to the control board. All told, the custom components have taken this once relatively mid-range 3D printer and turned it into something that looks like it wouldn’t be out of place on the International Space Station.

While custom 3D printer builds like this still trickle in from time to time, we’re seeing far fewer now than we did back when machines like the 3D20 hit the market. Most people are more than satisfied with commercial entry-level desktop printers, and aren’t looking for yet another project to tinker with. There’s nothing wrong with that, though we certainly wouldn’t complain if the recent interest into more advanced high-temperature filaments triggered something of a bespoke 3D printer renaissance.

source https://hackaday.com/2020/11/14/dremel-3d20-printer-gets-modern-overhaul/

Dremel’s attempt at breaking into the 3D printer market back in 2014 was respectable, if not particularly exciting. Rather than design their own printer, their 3D20 “Idea Builder” was a lightly customized Flashforge Dreamer (itself a Makerbot Replicator clone) with a new warranty and support contract tacked on. It wasn’t necessarily the 3D printer of choice for the hacker and maker crowd, but it was a fairly solid option for folks who wanted a turn-key experience.

[Chris Chimienti] says he got about 1,000 hours of printing out of his 3D20 before it gave up the ghost. Given the age of the machine and its inherent limitations, he decided to use the Dremel’s carcass as the base for a very impressive custom 3D printer with all the modern bells and whistles. He kept the enclosure, rods, bearings, and the stepper motors, but pretty much everything else was tossed out. Some of the replacements are off-the-shelf parts, but it’s the custom designed elements on this build that really help set it apart.

Under the machine, [Chris] has installed a new power supply and a Duet 2 WiFi controller which itself is connected to the new LCD control panel on the front. There’s an external case fan to keep the electronics cool, but otherwise things look a lot neater under the hood than they did originally.

Moving upwards, he’s designed a gorgeous adjustable print bed and a new extruder assembly that cleverly uses RJ45 jacks and Ethernet cables to connect back to the control board. All told, the custom components have taken this once relatively mid-range 3D printer and turned it into something that looks like it wouldn’t be out of place on the International Space Station.

While custom 3D printer builds like this still trickle in from time to time, we’re seeing far fewer now than we did back when machines like the 3D20 hit the market. Most people are more than satisfied with commercial entry-level desktop printers, and aren’t looking for yet another project to tinker with. There’s nothing wrong with that, though we certainly wouldn’t complain if the recent interest into more advanced high-temperature filaments triggered something of a bespoke 3D printer renaissance.

source https://hackaday.com/2020/11/14/dremel-3d20-printer-gets-modern-overhaul/

Hallowe’en may be over for another year, but that just means you’ve got more time to prepare your build for next time. [gocivici] has a fun twist on the classic mirror scare that might be just up your alley.

The build starts with an old black and white TV, hooked up to a Raspberry Pi 3. The Pi films the scene in front of the television through a camera secreted into the screen’s headphone jack, and displays it on screen. The camera feed is run through OpenCV, which runs face and eye detection algorithms to determine when a person is looking at the screen. Based on a basic timer script, when a viewer has looked long enough, a ghostly apparition is displayed, lurking behind the viewer. When the user looks over their shoulder, the apparition quickly disappears, as per the classical horror trope.

It’s a fun build that would make an excellent set piece for your next Hallowe’en party. For extra effect, be sure to secret it down a dark hallway with some IR LEDs illuminating the scene for the camera only. If you prefer something with a little more whimsy, consider these animated singing pumpkins instead. Video after the break.

source https://hackaday.com/2020/11/13/haunted-tv-does-mirror-scares-with-raspberry-pi/

Over the past years, the trend has become to ditch anything with wires. This has led to many people dropping wired earphones and headphones for wireless (Bluetooth) versions. Yet along with the freedom from having the wires snagged on something and having earphones painfully torn out of your ears comes the very real risk of having them drop out of your ears to land potentially very inconvenient.

In Japan this has led to a big issue for railway companies, where throngs of commuters will often accidentally drop possessions onto the tracks. Staff members will then use a mechanical claw (‘magic hand’) to fetch them without having to risk their life by jumping down. With small items such as wireless earphones, this is however not so easy. With 947 cases of dropped earphones in the period of July-September in just the Tokyo area, this has led to desperate staff members coming up with new methods of easily retrieving the small gadgets.

Solutions range from putting something sticky like tape at the end of a stick, to modifying vacuum cleaners. Most recently Tokyo railway company JR East has collaborated with Panasonic to develop a vacuum cleaner-like device that is especially designed to easily retrieve such small items from the tracks, according to the Japan Times article.

The embedded video (also found after the break) from a Japanese broadcaster describes the issue in detail, along with tips on how to properly wear earphones so that they’re far less likely to fall out when you’re waiting on the tram or walking down the street. While it’s possible to fetch your dropped wireless earphones from the tracks, having someone step on it right after it falls out of your ear on the street is less easy to recover from.

source https://hackaday.com/2020/11/13/wireless-earphones-and-getting-them-back-after-they-fall-on-tram-tracks/

Oregon State University must be a pretty good place to go to school if you want to hack on robots. Their robotics club, which looks active and impressive, has a multi-part video series on how to solder surface mount components that is worth watching. [Anthony] is the team lead for their Mars Rover team and he does the job with some pretty standard-looking tools.

The soldering station in use is a sub-$100 Aoyue with both a regular iron and hot air. There’s also a cheap USB microscope that looks like it has a screen, but is covered in blue tape to hold it to an optical microscope. So no exotic tools that you’d need a university affiliation to match.

We agree with [Anthony’s] order of parts. He does components that only have bottom pads first. Then he does the remaining difficult multi-lead components followed by the passives. However, for learning, it would probably be best to get used to soldering some easy components first.

He uses hot air to do the components with bottom-only pads. This is a great way to do it, although we’ve sometimes used nearby pads to inject heat under a part when we didn’t have hot air handy or were too lazy to use it. [Anthony’s] method is to tin the pads and then remove most of it with solder wick. He uses some extra solder to the wick to prime it, although we often use flux for the same reason. He uses the hot air gun but not solder paste, so you don’t have to worry about storing paste to use these techniques.

Doing these parts first makes it easier to control the hot air flow since you don’t have to worry about dislodging other nearby parts you haven’t placed yet. He doesn’t use hot air for the other components that have exposed leads.

Even if you’ve done a lot of SMD soldering, you can always pick up new tips and tricks. There’s lots of flux, of course, and careful alignment before you secure the component down. We know the feeling of leaving a bad solder joint long enough to go secure the other pads and then cleaning it up at the end.

We figure [Anthony] might do well at our annual SMD Challenge although we admit using our tools is what makes it a challenge. Of course, the big trick isn’t always building something new with surface mount components. It is repairing them.

source https://hackaday.com/2020/11/13/robotics-club-teaches-soldering/

Video blogger and display technology guru [Fran Blanche] has discovered a splendid retro-tech alphanumeric display from 1910. (Video, embedded below.)

We have always enjoyed her forays into old and unusual displays, including her project researching and reverse engineering an Apollo DSKY unit. This time [Fran] has dug up an amazing billboard from the early 20th century. It was built by the Rice Electric Display Company of Dayton Ohio, and operated in Herald Square for about two years. Requiring $400,000 in 1910-US-dollars to build, this was clearly an Herculean effort for its day and no doubt is the first example of selling advertising time on a computer-controller billboard. It boasts characters that are about 1.3 m tall and 1 m wide which can display letters, numbers, and various punctuation and symbols. These are arrayed into a 3-line 18-character matrix that is about 27 x 4 meters, and that’s up only a third of the total billboard, itself an illuminated and dynamic work of art.

There are quite a few tantalizing details in the video, but a few that jumped out at us are the 20,000 light bulbs, the 40 Hz display update rate, the 150 km of wire used and the three month long installation time. We would really like to learn more about these two 7.5 kW motorized switch controllers, how were they programmed, how were the character segments arranged, what were their shapes?

In the video, you can see triangles arranged in some pattern not unlike more modern sixteen segment displays, although as [Fran] points out, Mr Rice’s characters are more pleasing. We hope [Fran] can tease out more details for a future video. If you have any ideas or knowledge about this display, please put them in the comments section below. Spoiler alert after the video…

…this display is no longer standing.

source https://hackaday.com/2020/11/13/fran-finds-four-foot-alphanumeric-displays-from-1910/

The Raspberry Pi Compute Module 4 has got many excited, with a raft of new features bringing exciting possibilities. However, for those used to the standard Raspberry Pi line, switching over to the Compute Module form factor can be daunting. To show just how easy it is to get started, [timonsku] set about producing a quick and dirty carrier board for the module at home.

The Twitter thread goes into further detail on the design of the board. The carrier features HDMI, USB-A and USB-C ports, as well as a microSD slot. It’s all put together on a single-sided copper PCB that [timonsku] routed at home. The board was built as an exercise to show that high-speed signals and many-pin connectors can be dealt with by the home gamer, with [timonsku] sharing tips on how to get the job done with cheap, accessible tools.

The board may look rough around the edges, but that’s the point. [timonsku] doesn’t recommend producing PCBs at home when multi-layer designs can be had cheaply from overseas. Instead, it serves to show how little is really required to design a carrier board that works. Even four-layer boards can be had for under $10 apiece now, so there’s never been a better time to up your game and get designing.

For those eager to learn more about the CM4, we’ve got a full breakdown to get you up to speed!

source https://hackaday.com/2020/11/13/easy-carrier-board-for-the-compute-module-4-shows-you-can-do-it-too/

Calculating three-dimensional position from two-dimensional projections are literal textbook examples in geometry, but those examples are the “assume a spherical cow” type of simplifications. Applicable only in an ideal world where the projections are made with mathematically perfect cameras at precisely known locations with infinite resolution. Making things work in the real world is a lot harder. But not only have [Jingtong Li, Jesse Murray et al.] worked through the math of tracking a drone’s 3D flight from 2D video, they’ve released their MultiViewUnsynch software on GitHub so we can all play with it.

Instead of laboratory grade optical instruments, the cameras used in these experiments are available at our local consumer electronics store. A table in their paper Reconstruction of 3D Flight Trajectories from Ad-Hoc Camera Networks (arXiv:2003.04784) listed several Huawei cell phone cameras, a few Sony digital cameras, and a GoPro 3. Video cameras don’t need to be placed in any particular arrangement, because positions are calculated from their video footage. Correlating overlapping footage from dissimilar cameras is a challenge all in itself, since these cameras record at varying framerates ranging from 25 to 59.94 frames per second. Furthermore, these cameras all have rolling shutters, which adds an extra variable as scanlines in a frame are taken at slightly different times. This is not an easy problem.

There is a lot of interest in tracking drone flights, especially those flying where they are not welcome. And not everyone have the budget for high-end equipment or the permission to emit electromagnetic signals. MultiViewUnsynch is not quite there yet, as it tracks a single target and video files were processed afterwards. The eventual goal is to evolve this capability to track multiple targets on live video, and hopefully help reduce frustrating public embarrassments.

[IROS 2020 Presentation video (duration 14:45) requires free registration, available until at least Nov. 25th 2020.]

source https://hackaday.com/2020/11/13/tracking-drone-flight-path-via-video-using-cameras-we-can-get/