Slim RGB Matrix Puts LEDs Inside The PCB

December 7, 2020 by Danie Conradie 16 Comments

Sometimes all that’s required to build something interesting is to put the same old pieces together differently. [Sayantan Pal] did this for the humble RGB LED matrix, creating an extra-thin version by recessing WS2812b NeoPixel LEDs inside a PCB.

The popular WS2812B is 1.6 mm in height, which happens to be the most commonly used PCB thickness. Using EasyEDA, [Sayantan] designed a 8×8 matrix with modified WS2812B footprints. A slightly undersized cutout was added to create a friction-fit for the LEDs, and the pads were moved to the back side of the panel just outside the cutout, and their assignment were flipped. The PCB is assembled face down, and all the pads are soldered by hand. Unfortunately this creates rather large solder bridges which slightly increases the overall thickness of the panel, and is probably also unsuitable for production with conventional pick-and-place assembly.

We’ve seen some similar methods with PCB assemblies that use layered PCBs. Manufacturers are starting to even embed components inside multilayer PCBs.

A UV Curing Wand For Everyone

December 6, 2020 by Matthew Carlson 12 Comments

The average person’s experience with an ultraviolet (UV) wand is getting a cavity at the dentist. However, anyone with a resin-based 3d printer knows how important a UV curing system is. Often times some spots on a print need a little bit of extra UV to firm up. [Mile] has set out to create an open-source UV curing wand named Photon that is cost-effective and easy to build.

What’s interesting here is that there are dozens if not hundreds of UV curing systems ranging from $5 LED flashlights to larger industrial flood systems. [Mile] dives right in and shows the trade-offs that those cheaper modules are making as well as what the commercial systems are doing that he isn’t. [Mile’s] Photon wand tries to be energy efficient with more irradiated power while staying at a lower cost. This is done by carefully selecting the CSP LEDs instead of traditional wire-bonded and making sure the light source is properly focused and cooled. From the clean PCB and slick case, it is quite clear that [Mile] has gone the extra step to make this production-friendly. Since there are two industry-standard wavelengths that resins cure at (364nm and 405nm), the LED modules in Photon are user-replaceable.

What we love about this project is looking past what is readily available and diving deep. First understanding the drawbacks and limitations of what is there, then setting a goal and pushing through to something different. This isn’t the first UV curing tool we’ve seen recently, so it seems there is a clear need for something better that’s what is out there today.

Continue reading “A UV Curing Wand For Everyone” →

Sierpinski PCB Christmas Tree

December 4, 2020 by Rich Hawkes 3 Comments

It’s holiday time again! And that means it’s time to break out the soldering iron and the RGB LEDs! If you’re going to make a custom PCB to put those LEDs on, you’ll notice that you get few copies of your PCB in your order, so, might as well design it such that you can combine them all together into a single Sierpinski Christmas Tree, just like [Landon Carter] did.

Each PCB “tree” has three connections which can be used as either inputs or outputs by soldering one of two bridge connections on the PCB. The power and signal goes up and down through the tree, rather than across, so the connections go one on the top of the tree and two on the bottom. This way, each tree in the triangle can easily be connected, and each triangle can be easily connected to another. Each individual tree has three WS2812b-mini addressable RGB LEDs and the tree is controlled by an external Arduino.

The first order of 10 PCBs came in, which makes a 9 member tree – next up is a 27 member tree. After that, you’re going to need some pretty high vaulted ceilings in order to put these on the wall. On the upside, though, once the holidays are over, everything can be easily disconnected and packed away with the rest of the decorations. If you, too, are interested in RGB LED decorations, there are a few on the site for your perusal.

Transforming Work Light Is More Than Meets The Eye

December 4, 2020 by Tom Nardi 3 Comments

While it does use the same M12 batteries, this impeccably engineered work light isn’t an official Milwaukee product. It’s the latest creation from [Chris Chimienti], who’s spent enough time in the garage and under the hood to know a thing or two about what makes a good work light. The modular design not only allows you to add or subtract LED panels as needed, but each section is able to rotate independently so it points exactly where you need it.

Magnets embedded in the 3D printed parts mean the light modules not only firmly attach to one another, but can be stuck to whatever you’re working on. Or you could just stack all the lights up vertically and use the rocket-inspired “landing legs” of the base module keep it vertical. Even if the light gets knocked around, the tension provided by rubber bands attached to each fold-out leg means it will resist falling over. In the video after the break [Chris] says the little nosecone on top is just for fun and you don’t have to print it, but we don’t see how you can possibly resist.

The same PCB is used on both ends of the light modules.

Of course, 3D printed parts and magnets don’t self-illuminate. The LED panels and switches are salvaged from cheap lights that [Chris] found locally for a few bucks, and a common voltage regulator board is used to step the 12 volts coming from the Milwaukee battery down to something the LEDs can use. He’s designed a very slick reversible PCB that’s used on either end of each light module to transfer power between them courtesy of semi-circular traces on one side and and matching pogo pins on the other.

As we saw in his recent Dremel 3D20 rebuild, [Chris] isn’t afraid to go all in during the design phase. The amount of CAD work that went into this project is astounding, and serves as fantastic example of the benefits to be had by designing the whole assembly at once rather than doing it piecemeal. It might take longer early on, but the final results really speak for themselves.

Continue reading “Transforming Work Light Is More Than Meets The Eye” →

Alfa Romeo Gauge Cluster Gets A Fresh Set Of LEDs

November 26, 2020 by Tom Nardi 14 Comments

On older vehicles, if you noticed that the lights had gone out behind one of your gauges, you knew it was time to snake your hand back there and replace the little incandescent bulb that had given up the ghost. But what are you supposed to do if you’re seeing the same problem on a modern vehicle that’s already made the leap to LED dash lighting? That’s what [Tysonpower] recently had to find out when the fuel indicator on his Alfa Romeo Giuletta QV went dark.

In the video after the break, [Tysonpower] details how to remove the instrument cluster from the Giuletta’s dash, which we imagine would be a useful little tutorial for anyone who owns the same vehicle. Once he has it out on the bench, he strips it down to the bare PCB and starts (literally) poking around.

He eventually noticed that if he pushed on the board near the fuel indicator he could get the appropriate 3528 SMD LED to light up, but touching up the solder joints didn’t seem to fix the issue. Assuming the LED must be defective internally, he simply replaced it and all was good again.

Well, not exactly. The light produced by the new part didn’t match the color or brightness of the other dozen or so white LEDs that were installed on the board, so [Tysonpower] decided to just dive in and replace them all. While it obviously took a lot more time and effort, he says the end result is that the instrument cluster looks noticeably brighter and crisper when driving at night. Not bad for an afternoon’s work and a couple bucks worth of LEDs.

Most of the time, when we see somebody messing around behind the dash it’s because they intend on replacing the original instruments with something more capable. But projects like this, which add just a touch of refinement to the existing hardware, prove that stock components aren’t always a disappointment.

Continue reading “Alfa Romeo Gauge Cluster Gets A Fresh Set Of LEDs” →

RGB Party Bike Flashes With The Beat

November 22, 2020 by Lewin Day 9 Comments

One of the biggest dangers to a cyclist is not being seen at night. To counteract this, all manner of lighting and reflective gear is available to help ensure bicycles are seen on the streets. Of course, you don’t have to stop at the purely practical. [TechnoChic] decided to have some fun with her ride, festooning her party bike with many, many LEDs.

As you’d expect, the RGB illuminations are thanks to WS2812B LED strips. Running the show is a trio of Arduino Nano 33 IoTs – one for the LEDs on the bike’s frame, the other two mounted on the front and back wheels respectively. This allowed for the easy control of LEDs on the spokes without having to pass data and power lines to the rotating wheels. The LEDs on the frame are even music-reactive, with the Arduino sampling music input via one of its analog-to-digital converters.

Paired with a boombox on the bike, the build makes for a great way to hype up group rides through the city at night. We can imagine such a bike being an absolute hit at Critical Mass, though you’ve probably gotta add a laser or glitter cannon if you’re going to draw attention at Burning Man. If you’re tired of pedaling, you might consider an electric conversion, too. Video after the break.

Continue reading “RGB Party Bike Flashes With The Beat” →

Illuminated 3D Printed Guitar Is Ready To Rock

November 14, 2020 by Tom Nardi 6 Comments

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.

The white ABS of the guitar body helps diffuse the LEDs.

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.

Continue reading “Illuminated 3D Printed Guitar Is Ready To Rock” →