Neon Mermaid

This page is WIP. Among other things, it still lacks pictures and (links to) design files.

Inspired by neon-syrenka.svg from the current edition of our website (thanks, q3k! :3), a physical pseudo-neon, made from PMMA, HDF, addressable LEDs, and controllable using WLED

There's a standard WLED interface at http://hs-pseudo-neon.bms.waw.hackerspace.pl/; while physically it's all just a single LED strip, the ring and mermaid itself are configured to be controllable separately

This section is WIP.

The mermaid is hung up using a chain bolted in three points on the back and passing through a piece of aluminum tubing.

Because of a design fault in the electronics box construction - the end of the sidewall in which C14 receptacle is placed is not supported from all sides - additional care must be taken when unplugging the power cable (holding down the end of the wall is enough). This won't be rectified in the current iteration of the project, as future plans (already in motion) will require a redesign of the electronics box anyway.

It can power additional devices, eg. other LED strips, from XT60 connectors on the back. Since most LED strips at the hackerspace are powered using 5V, the 24V connector is plugged to avoid accidental release of magic smoke.

A stack of laser-cut PMMA and HDF. Going from the front to the back:

1. full-circle of PMMA at the front
2. HDF circle mostly painted black, with holes in the “desired” light shape, and manually sanded PMMA inserts to help diffuse the light.
3. 4 layers of HDF forming a simplified path for the LED strip to take.
4. backing layer of PMMA, identical to the front one, to help keep the LED strip in place, with two additional holes (or at least that was the intention…) for the ends of the strip.

They're all screwed together with M4 screws and nylock nuts to make disassembly possible, even if somewhat annoying.

Additionally, there's a PMMA box containing the two power supplies and electronics on the back.

Most of these are substantially over-specced, chosen because of a combination of factors:

• (perceived) quality
• reliability
• what was available at hand
• trust issues with step-down converters

Reliability was the especially important factor here - I wanted this project to be delivered in operational state for WHY 2025 camp, where it would spend almost a week hung high up in a tent, and I *really* did not want to spend time hunting for components and repairing things in the field.

This resulted in the following things being chosen:

• 5 meter/70 segments total 24V RGBW LED strip
  • chosen because I had good experience - bright, stable, nice colors - with this particular LED strip “model” in another (not yet finished) project
  • allegro or some random online store
  • doesn't have a particular model name or anything; might be difficult to source later
  • I have 1 extra strip “spare”
• 24V PSU: Mean Well RSP-320-24
  • overspecced, the strip takes around 100W at most, but that gives us plenty of headroom to power other things in the future
• 5V PSU: Mean Well LRS-50-5
  • overspecced, powers just the esp32 (if nothing else is plugged in the back)
  • chosen because I literally had a small step-down converter, to convert from 24V to 5V, die on me a few days before camp
  • at WHY2025, CebulaCamp, and - at the time of writing - at the hackerspace used to power the 4× 1m LED led strips in white diffusing tubes
• random insert-model-here esp32 module