From resin casting to Open Tech Summit and much more — time for another monthly update!

9 min readOct 5, 2022

Hey there! And welcome to another monthly update about my LED projects, what progress I made and what comes next! A lot has happened in the last month, so let’s directly dive into the details.


I had the chance to test GlowCore for the first time with LED strips other than the WS2812B based LED strips I used so far. While I was visiting Sudo Room in Oakland and helped prepare an event where people could modify their bikes with LEDs, I tested a bunch of diverse LED strips. And with the exception of some very old LEDs, they all have been supported in WLED and therefore worked just expected. I only had to update the LED settings in WLED and select the correct type of LEDs — and voilla, it glows.

In addition, I also updated the GlowCore PCB design with some further improvements. The screw terminals are now larger and therefore easier to use with thicker wires, software-controlled relays can connect & disconnect the 5V and external 3.3V devices from power and the GPIO pin selection has also been updated. The VBUS pin (USB voltage) is also accessible now, which is gonna be super useful for battery-powered projects. Speaking off…

I also started working on a battery extension, which makes it possible to play around with battery-powered LED projects with ease! A simple board with a voltage converter, battery management, and that board automatically turns off the voltage converter if USB-C power is connected to GlowCore. So the battery doesn’t get drained and only gets charged instead, as long as USB-C is connected. And like GlowCore it also can be easily connected and disconnected using the screw terminals, without having to solder anything.

Waterslide decals

In August I explored stickers for adding text and images to the cases of my LED projects. And while this looked way better than extruding the text directly into the case, it still wasn’t ideal. Once applied, the sticker position and angle couldn’t be corrected, and the color difference in comparison to the case was still very noticeable. So I explored another new method: waterslide decals. And oh boy, that already looks much better. Plus, the waterslide decal can be moved around the case into the ideal position, as long as the surface is still wet. So to summarize, an overall better replacement for stickers.

Custom packaging

I also experimented with making my first custom packaging design — and producing it in the local hackspace here in Berlin, xHain. I ended up using a laser cutter for that. And the second try looked already very nice and like a decent way to cut a handful of packages that way.


After I was frustrated about the power converter electronics not working properly, despite multiple attempts with different converter chips from the same chinese manufacturer, I am happy to announce — I finally found a solution, which works just the way it was supposed to! Yesss!

What solved the problem? Well… following the advice of a friend in San Francisco and switching to a power converter from a known western brand — like Texas Instruments. Yes, the power converter chip from TI is more expensive than the one from the chinese brand, but most importantly: it works, perfectly fine and stable!

To both make it easier to upgrade GlowSign to the battery-powered version, as well as to make the testing process of the battery extension electronics easier (when I didn’t know yet if the chip from TI will fix my power conversion problem), I separated the battery electronics to a separate PCB. Which also turned out to be super useful for testing the battery extension electronics for other projects as well: like MagiqWand (where it also works just as expected). I am sooo glad that this issue is finally solved and that I can now finalize the electronics of my battery-powered projects, plan new ones for the coming months and share with others how to easily build their own battery-powered LED projects.


Coming back to USB-C-powered projects: this is what the finalized version of GlowTower looks like, fully assembled! Wonderful, right? Turned out, the GlowTower DIY set that a friend assembled with me in a workshop and which didn’t work directly as planned — was assembled wrong. And since the friend was in a hurry last time, I also didn’t think about triple checking the direction of the LED strips, and how they are soldered to the other PCBs. But that caused in the end the issue. But great to see that the LED lamp works perfectly fine now and that the friend is happy with it at home.

Resin casting

To produce multiple cases both for GlowTower and GlowLight, I started experimenting with resin casting in August. One of the things I learned from my first failed casts — I needed a syringe, to push the epoxy resin into the entire mold. And I also realized that I should 3D print negatives to make two perfect halves of a silicone mold. And so I did. Was the result better? Well… yes, I guess. But sadly still by far not ideal. I got a lot more air and therefore bubbles this time into the silicone mold, partially because I used the syringe I think. Also, the silicone started to bend, under the pressure of the epoxy resin. And with nothing preventing it from bending, I had a few mm extra thickness in the parts, which made them unusable. So what now? Well for once I need to build a case surrounding the silicone mold, that makes sure the silicone is under pressure from all sides and doesn’t bend. And for removing the air bubbles: ideally, I would have a working pressure tank for resin casting. Technically we do have a pressure tank at xHain, which could be converted into a casting pressure tank. But I don’t know for sure what exact parts are needed for that, where to get them and how much they would cost. And the pressure tank already started to drive me nuts. So for now, I will try to optimize my resin casting process without the pressure pot. People on the internet say one can also make bubble-free casts without a pressure pot — and also proved it for smaller objects. So let’s see if I can also make it work for bigger objects.

New website

Last month I launched the new online shop — There you can find all my finished LED projects as DIY kits. But the idea from the beginning was to also have a separate main website, informing and exciting people about my LED projects — as well as providing an easy-to-navigate place for all the documents related to my projects (manuals, FAQ, tutorials, and more). So started building this new website, going from having the first design to building the actual website. But since I didn’t want to code everything from scratch in HTML/CSS/JS, or learn React or a similar framework (for now at least), I decided to use TeleportHQ for building the new main website. It’s a website builder, similar to Webflow, but which I prefer over Webflow (which I have used in the past for a long time), both because of the features they offer, as well as their pricing model. I am not yet finished with the new website but will do so in October and launch the website.

Meetup group

I am also happy to announce that I launched the LED Makers Berlin meetup group — and also just announced the first meetups: a biweekly LED co-working evening, as well as a biweekly beginner workshop to help people build their first LED projects. In the LED co-working group, we meet to work together on LED projects. A great way to make progress and exchange with others. While at the beginner workshop I teach people how they can get started with building their own LED projects. Both are in-person events at xHain. Looking forward to them already :)

OpenTech Summit

And speaking of events — I also joined OpenTech Summit, a conference in Berlin about open source hardware projects. While the event was smaller than I originally expected, it was still a great time, and some lovely and very interesting people and talks there. Also: this was the first time in years that I have given a talk as well, telling people why LEDs are a great introduction to industrial design — and summarizing my last few years of getting into LEDs and industrial design. Overall I am really glad I was able to join OpenTech Summit and was invited to give a talk. And I am already looking forward to OpenTech Summit next year, hopefully, with even more people — so more people learn about all the cool open source hardware projects out there and why it’s important to support open hardware.

What’s next in October?

But enough of what last month — let’s talk about the future — let’s talk about what’s next in October! First, I will get the resin casting to work properly, so I can produce case parts for my LED lamps that way. Next, I will finish the new website, including quick-start guides, manuals, and FAQs around my LED projects. In addition, I will also see that I make GlowSign available as a DIY kit on my online store as well. And of course, I will organize the first LED co-working meetups and beginner workshops — and possibly also the first more advanced workshops around PCB design and product design with CAD software.

Regarding the software that runs on all my LED projects: I need to modify WLED, to both implement a deep sleep mode, but also the option to turn on/off wifi with the press of a button, and also show a “battery empty” warning, once the battery reaches 3v — to make sure it doesn’t discharge to a level that harms the battery health.

And in addition, it’s also time for me to start more actively searching for possible team members/co-founders, someone who has a passion for business development and getting more people excited about industrial design, with open source LED products.

So yeah, a lot of things to do in October. But I am really looking forward to them. See you next time, in the next monthly update!




Hey, Marco here! Maker and LED enthusiast. Loves learning new skills and exploring the world.