Making A Mega LED Desk

March 2, 2017 by James Hobson 37 Comments

Few things beat a sturdy, home-built desk — especially when it’s jam-packed with over 1200 WS2812 LEDs.

[nolobot] and his bother struggled with setting up and squaring-off the t-slotted, extruded aluminium frame which makes up the desk. He recommends practicing with a smaller frame for anyone else attempting a similar build. The surface of the desk has a few inches between the polycarbonate top and the 1/4″ plywood painted black serving as the substrate for the LEDs. Those LEDs come in strip form but still required several hundred solders, and wiring headaches in an attempt to make future upgrades manageable. Dozens of support bolts with adjustable feet support the desk surface throughout. These all had to be individually adjusted and can be made out if you look closely at the demo videos.

An Arduino Mega controls the LEDs with the help of the FastLED library. Custom code was necessary because one of the major issues [nolobot] faced was the power draw. 1200 LEDs at 5V draw quite a bit of current, so the LEDs were coded to peak at about 50% brightness. The matrix was split into different banks, while also limiting the 40A PSU to only 15A.

Continue reading “Making A Mega LED Desk” →

Beautiful Linear RGB Clock

February 18, 2017 by Elliot Williams 12 Comments

Yup, another clock project. But here, [Jan] builds something that would be more at home in a modern art museum than in the dark recesses of a hacker cave. It’s not hard to read the time at all, it’s accurate, and it’s beautiful. It’s a linear RGB LED wall clock.

You won’t have to learn the resistor color codes or bizarre binary encodings to tell what time it is. There are no glitzy graphics here, or modified classic timepieces. This project is minimal, clean, and elegant. Twelve LEDs display the hours, six and nine LEDs take care of the minutes in add-em-up-coded decimal. (It’s 3:12 in the banner image.)

The technical details are straightforward: WS2812 LEDs, an Arduino, three buttons, and a RTC. You could figure that out by yourself. But go look through the log about building the nice diffusing plexi and a very clean wall-mounting solution. It’s the details that separate this build from what’s hanging on our office wall. Nice job, [Jan].

Chronio DIY Watch: Slick And Low Power

February 15, 2017 by Elliot Williams 19 Comments

[Max K] has been testing the battery life of his self-designed watch under real-world conditions. Six months later, the nominally 3 V, 160 mAh CR2025 cell is reading 2.85 V, so the end is near, but that’s quite a feat for a home-engineered smart watch.

We’ve tipped our hats to the Chronio before in this Hacklet, but now that the code is available, as well as the sweet 3D-printed case files, it’s time to make your own. Why? It looks sweet, it plays a limited version of Flappy Bird (embedded below), and six month’s on a button cell is a pretty great accomplishment, considering that it’s driving a 96×96 pixel LCD display.

The Chronio is more than inspired by the Pebble watch — he based his 3D model directly on theirs — so that’s bound to draw comparisons. The Pebble is color, and has Bluetooth and everything else under the sun. But after a few weeks away from a power socket, ask a Pebble wearer what time it is. Bazinga!

Continue reading “Chronio DIY Watch: Slick And Low Power” →

Wood And Rubber Band Pinball

February 12, 2017 by Rich Hawkes 9 Comments

As pinball has evolved, it has gone from a simple gravity based game to an electromechanical one. As the 20th century came to a close, pinball games added digital elements as well, matrix displays replaced electromechanical scoreboards, and LEDs replaced incandescent bulbs. While the game got more creative as new technologies became available, the basics of the pinball never changed – keep the ball alive using your skill with the flippers (and the occasional nudge.) [Garagem Fab Lab] has taken the basics of the pinball machine and, with some wood and elastic bands, has created a very nice desktop pinball machine.

The plans for the game require getting the wood cut by a CNC mill, but they could probably be easily created using a jigsaw. Instead of electrical buttons and solenoids, pieces of wood push the flippers out and elastics reset them when released. The bumpers, too, are simple dowels with rubber bands wrapped around them. The launching mechanism is a bit of bungee cord tied onto a piece of wood and used like a flipper to speed the ball into the play area.

The build is a throwback to the earliest pinball machines. Sure, there’s no reaction from the bumpers when they’re hit, they’re just passive, but the game looks fun. It would be a great base to add in some sensors, a microcontroller, and a display to keep track of scores if one was so inclined. Other DIY pinball machines we’ve seen are this pinball game built with Meccano and lasers, as well as this completely 3D-printed machine.

DIY Wire Spooler With Clever Auto-Tensioning System

February 5, 2017 by Donald Papp 19 Comments

[Solarbotics] have shared a video of their DIY wire spooler that uses OpenBeam hardware plus some 3D printed parts to flawlessly spool wire regardless of spool size mismatches. Getting wire from one spool to another can be trickier than it sounds, especially when one spool is physically larger than the other. This is because consistently moving wire between different sizes of spools requires that they turn at different rates. On top of that, the ideal rate changes as one spool is emptying and the other gets larger. The wire must be kept taut when moving from one spool to the next; any slack is asking for winding problems. At the same time, the wire shouldn’t be so taut as to put unnecessary stress on it or the motor on the other end.

There aren’t any build details but the video embedded below gives a good overview and understanding of the whole system. In the center is a tension bar with pulleys on both ends though which the wire feeds. This bar pivots at the center and takes up slack while its position is encoded by turning a pot via a 3D printed gear. Both spools are motor driven and the speed of the source spool is controlled by the position of the tension bar. As a result, the bar automatically takes up any slack while dynamically slowing or speeding the feed rate to match whatever is needed.

Continue reading “DIY Wire Spooler With Clever Auto-Tensioning System” →

Plywood Steals The Show From Upcycled Broken Glass Art Lamps

February 4, 2017 by Elliot Williams 23 Comments

You can tell from looking around his workshop that [Paul Jackman] likes plywood even more than we do. And for the bases of these lamps, he sandwiches enough of the stuff together that it becomes a distinct part of the piece’s visuals. Some work with a router and some finishing, and they look great! You can watch the work, and the results, in his video embedded below.

The plywood bases also hide the electronics: a transformer and some LEDs. To make space for them in the otherwise solid blocks of wood, he tosses them in the CNC router and hollows them out. A little epoxy for the caps of the jars and the bases were finished. Fill the jars with colored glass, and a transparent tube to allow light all the way to the top, and they’re done.

Continue reading “Plywood Steals The Show From Upcycled Broken Glass Art Lamps” →

No-Etch: The Proof In The Bluetooth Pudding

February 2, 2017 by Elliot Williams 40 Comments

In a previous episode of Hackaday, [Rich Olson] came up with a new no-etch circuit board fabrication method. And now, he’s put it to the test: building an nRF52 Bluetooth reference design, complete with video, embedded below.

The quick overview of [Rich]’s method: print out the circuit with a laser printer, bake a silver-containing glue onto the surface, repeat a few times to get thick traces, glue the paper to a substrate, and use low-temperature solder to put parts together. A potential drawback is the non-negligible resistance for the traces, but a lot of the time that doesn’t matter and the nRF52 reference design proves it.

The one problem here may be the trace antenna. [Rich] reports that it sends out a weaker-than-expected signal. Any RF design folks want to speculate wildly about the cause?

Continue reading “No-Etch: The Proof In The Bluetooth Pudding” →