Author: Bryan Cockfield

1847 Articles

Casting Metal With A Microwave And Vacuum Cleaner

September 29, 2022 by 39 Comments

Metalworking might conjure images of large furnaces powered by coal, wood, or electricity, with molten metal sloshing around and visible in its crucible. But metalworking from home doesn’t need to use anything more fancy than a microwave, at least according to [Denny] a.k.a. [Shake the Future]. He has a number of metalworking tools designed to melt metal using a microwave, and in this video he uses them to make a usable aluminum pencil with a graphite core.

Before getting to the microwave kiln, the pencil mold needs to be prepared. A 3D-printed pencil is first created with the graphite core, and then [Denny] uses a plaster of Paris mixture to create the mold for the pencil. The 3D printed plastic is left inside the mold and placed in the first microwave kiln, which is turned on just enough to melt the plastic out of the mold, leaving behind the graphite core. From there a second kiln goes into the microwave to melt the aluminum.

Once the molten aluminum is ready, it is removed from the kiln and poured in the still-warm pencil mold. This is where [Denny] has another trick up his sleeve. He’s using a household vacuum cleaner to suck the metal into place before it cools, creating a rudimentary but effective vacuum forming machine. The result is a working pencil, at least after he wears down a few razor blades attempting to sharpen the metal pencil. For more information about how [Denny] makes these microwave kilns, take a look at some of his earlier projects.

Continue reading “Casting Metal With A Microwave And Vacuum Cleaner” →

A Drone For The Rest Of Us

September 29, 2022 by 23 Comments

As anyone who’s spent Christmas morning trying to shake a quadcopter out of a tree can attest, controlling these fast moving RC vehicles can be tricky and require a bit of practice to master. [Erik] wanted to simplify this a little bit so his children and friends could race with him, and the end result is a drone that only needs two inputs to fly.

The results of his experimentation with simplifying the controls resulted in a “speeder” type drone which attempts to keep a certain distance off of the ground on its own thanks to an extremely fast time-of-flight sensor. The pilot is then left to control the throttle and the steering only, meaning that [Erik] can use pistol-style RC controllers for these machines. They have some similarities to a quadcopter, but since they need to stay level in flight they also have a fifth propeller on the back, similar to an airboat. This allows for a totally separate thrust control than would normally be available on a quadcopter.

The resulting vehicle is immediately intuitive to fly, behaving more like an RC car than a quadcopter. This also required quite a bit of processing power to compute the proper roll and yaw from a single steering input, but after many prototypes the result is impressive, especially since it was also built to use FPV as a means of control. One of the videos below demonstrates this video, and looks extremely fun to fly, and we wouldn’t mind seeing a race with these types of speeders much like we saw in the past with a group of pod-racing quadrotors.

Continue reading “A Drone For The Rest Of Us” →

The NES Gets Its Own OS

September 28, 2022 by 20 Comments

Until recently, most video game systems didn’t need their own operating systems in order to play games. Especially in the cartridge era — the games themselves simply ran directly on the hardware and didn’t require the middleman of an operating system for any of the functionality of the consoles. There were exceptions for computers that doubled as home computers such as the Commodore, but systems like the NES never had their own dedicated OS. At least, until [Inkbox] designed and built the NES-OS.

The operating system does not have any command line, instead going directly for a graphical user interface. There are two programs that make up the operating system. The first is a settings application which allows the user to make various changes to the appearance and behavior of the OS, and the second is a word processor with support for the Japanese “Family Keyboard” accessory. The memory on the NES is limited, and since the OS loads entirely into RAM there’s only enough leftover space for eight total files. Those files themselves are limited to 832 bytes, which is one screen’s worth of text without scrolling.

While it might seem limited to those of us living in the modern era, the OS makes nearly complete use of the available processing power and memory of this 1980s system that was best known for Super Mario Bros. and Duck Hunt. It’s an impressive build for such a small package, and really dives into a lot of the hardware and limitations when building software for these systems. If you need more functionality than that, we’d recommend installing Linux on the NES Classic instead.

Continue reading “The NES Gets Its Own OS” →

24 Hours Of Le Airplanes

September 27, 2022 by 22 Comments

There’s no more famous road endurance race than the 24 Hours of Le Mans, where teams compete to see how far they can drive in a single 24-hour window. The race presents unique challenges not found in other types of racing. While RC airplanes may not have a similar race, [Daniel] a.k.a. [rctestflight] created a similar challenge for himself by attempting to fly an RC airplane non-stop for as long as he could, and a whole host of interesting situations cropped up before and during flight.

In order for an RC plane to fly for an entire day, it essentially needs to be solar powered. A large amount of strategy goes into a design of this sort. For one, the wing shape needs to be efficient in flight but not reduce the amount of area available for solar panels. For another, the start time of the flight needs to be balanced against the position of the sun in the sky. With these variables more or less fixed, [Daniel] began his flight.

It started off well enough, with the plane in an autonomous “return to home” mode which allowed it to continually circle overhead without direct human control. But after taking a break to fly it in FPV mode, [Daniel] noticed that the voltage on his battery was extremely high. It turned out that the solar charge controller wasn’t operating as expected and was shunting a large amount of solar energy directly into the battery. He landed and immediately removed the “spicy pillow” to avoid any sort of nonlinear event. With a new battery in the plane he began the flight again.

Even after all of that, [Daniel] still had some issues stemming from the aerodynamic nature of this plane specifically. There were some issues with wind, and with the flight controller not recognizing the correct “home” position, but all in all it seems like a fun day of flying a plane. If your idea of “fun” is sitting around and occasionally looking up for eight and a half hours. For more of [Daniel]’s long-term autonomous piloting, be sure to take a look at his solar tugboat as well.

Continue reading “24 Hours Of Le Airplanes” →

Trombone Controls Virtual Trombone

September 27, 2022 by 5 Comments

Guitar Hero was a cultural phenomenon a little over a decade ago, and showed that there was a real fun time to be had playing a virtual instrument on a controller. There are several other similar games available now for different instruments, including one called Trombone Champ that [Hung Truong] is a fan of which replaces the traditional guitar with a trombone. The sliding action of a trombone is significantly different than the frets of a guitar, making it a unique challenge in a video game. But an extra challenge is building a controller for the game that works by playing a real trombone.

Unlike a guitar which can easily map finger positions to buttons, mapping a more analog instrument like a trombone with its continuous slide to a digital space is a little harder. The approach here was to use an ESP32 and program it to send mouse inputs to a computer. First, an air pressure sensor was added to the bell of the trombone, so that when air is passing through it a mouse click is registered, which tells the computer that a note is currently being played. Second, a mouse position is generated by the position of the slide by using a time-of-flight sensor, also mounted to the bell. The ESP32 sends these mouse signals to the computer which are then used as inputs for the game.

While [Hung Truong] found that his sensors were not of the highest quality, he did find the latency of the control interface, and the control interface itself, to be relatively successful. With some tuning of the sensors he figures that this could be a much more effective device than the current prototype. If you’re wondering if the guitar hero equivalent exists or not, take a look at this classic hack from ’09.

Continue reading “Trombone Controls Virtual Trombone” →

3D Printing The Key To A Bass Clarinet

September 27, 2022 by 8 Comments

Playing music as part of a group typically requires that not only are all of the instruments tuned to each other, but also that the musicians play in a specific key. For some musicians, like pianists and percussionists, this is not terribly difficult as their instruments are easy to play in any key. At the other end of the spectrum would be the diatonic harmonica, which is physically capable of playing in a single key only. Other orchestral instruments, on the other hand, are typically made for a specific key but can transpose into other keys with some effort. But, if you have 3D printed your instrument like this bass clarinet from [Jared], then you can build it to be in whichever key you’d like.

The bass clarinet is typically an instrument that comes in the key of B flat, but [Jered] wanted one that was a minor third lower. Building a traditional clarinet is not exactly the easiest process, so he turned to his 3D printer. In order to get the instrument working with the plastic parts, he had to make a lot of the levers and keys much larger than the metal versions on a standard instrument, and he made a number of design changes to some of the ways the keys are pressed. Most of his changes simply revert back to clarinet designs from the past, and it’s interesting to see how simpler designs from earlier time periods lend themselves to additive manufacturing.

While [Jared] claims that the two instruments have slightly different tones, our amateur ears have a hard time discerning the difference. He does use a standard clarinet bell but other than that it’s impressive how similar the 3D printed version sounds to the genuine article. As to why it’s keyed differently than the standard, [Jared] points out that it’s just interesting to try new things, and his 3D printer lets him do that. We’d be happy to have another instrument in our 3D printed orchestra, too.

Continue reading “3D Printing The Key To A Bass Clarinet” →

Building An Old Guitar From A New One

September 27, 2022 by 3 Comments

Anyone who’s ever played guitar to at least the skill level required to form a terrible garage band knows the names of the most legendary guitars. The driving sound of the Gibson Les Paul played by Jimmy Page, the upside-down and smooth Fender Stratocaster from Jimi Hendrix, or the twangy Rickenbacker made famous by George Harrison are all lusted-after models. The guitar that [Frank] really wanted was a Danelectro DC59 and since they’ve been steadily creeping up in price, he decided to build his own.

The body of the clone guitar is hollow and made from effectively scrap wood, in this case plywood. As the original guitars were in fact famous for using the least expensive materials possible, this makes it a great choice for a clone. [Frank] made the guitar using almost exclusively hand tools and glued everything together, but did use a few donor parts from a modern Stratocaster-type guitar. With most of the rough shape of the guitar finished, it was time to add the parts that make the guitar sound the way that a real Danelectro should: the lipstick-style pickups. He purchased these completely separately as they are the most important part to get right to emulate the tone and feel of the original.

With everything finally soldered and assembled, [Frank] got right to work recording a sample audio track which is included at the end of the video. It certainly sounds like the original to our untrained ears, and for around $100 it’s not a bad value either. If you’d like to see a guitar built from the ground up without using another as a clone, take a look at this build which brings a completely original guitar into existence, entirely from scratch.

Continue reading “Building An Old Guitar From A New One” →