USB Powered French Cleat Showcase
Description
USB Powered French Cleat Showcase
I wanted to display my CO₂ guns in wall-mounted shadow boxes, but after closing the acrylic front, I ran into two problems:
- The guns were barely visible due to reflections.
- The velvet background appeared almost completely black.
The obvious solution was to add lighting, but I wanted it to remain completely hidden.
The First Idea
I immediately thought of:
* 5V COB LED strips
* 18650 Li-ion batteries
* a QIACHIP 433 MHz RF receiver for Home Assistant integration
A 3D-printed housing that sits on top of each frame was supposed to hide everything.
But the more I thought about it, the clearer it became to me that batteries would increase the complexity and result in a visible housing that would detract from the clean appearance of the display case.
It was also questionable whether the battery life would be sufficient.
So, no batteries! Power rails came to mind.
Power supply via the French cleat
Instead of installing a battery in each frame, I turned the French cleat itself into the power connection.
Both the wall mount and the frame mount are fitted with strips of self-adhesive copper tape.
When the display case is hung on the wall, it lights up immediately.
The Unexpected Problem
The first prototypes worked perfectly on the table.
However, once they were mounted on the wall, it turned out that the plastic warped, and the unevenness of the wall also prevented the copper strips from making contact.
I don’t know how many times I revised the design because I was determined to create an electrical connection without sliding contacts.
After numerous attempts, I had to admit that it wouldn’t work without sliding contacts, but I also wanted to finish the project and not wait for another commission.
The solution was surprisingly simple:
> Small pieces of 1 mm thick foam tape placed under the copper strip ensure constant contact pressure.
I also attached these rubber pieces under the copper tape at the edges where the rails meet.
This completely solved the problem without requiring spring-loaded contacts or additional components.
Concealed Electronics
The RF receiver is hidden behind the frame, and there isn’t much else in the way of electronics.
The 3mm COB LED strip produces a continuous line of light without visible LED hotspots, illuminating the interior evenly.
The display cases can be removed at any time and are immediately illuminated again when rehung.
The QIACHIP 433 MHz receiver can be integrated into Home Assistant via an RF bridge to enable remote control and automation.
Pistol Holder
The pistol holder was inspired by these projects:
- https://www.thingiverse.com/thing:5971455
- https://makerworld.com/de/models/470058-pistol-wall-mount#profileId-379532
The published mount is an independent design created from scratch in Fusion 360, utilizing the functional principles of the referenced projects.
The box purchased from AliExpress, Color C !
What was used
| Copper tape | 4 mm, self-adhesive |
| RF receiver | QIACHIP 433 MHz |
| 3mm LED strip | 5 V COB, 4000 K, 480 LEDs/m |
| USB-C snap-in socket |
| Foam tape | 1 mm thick |
| Heat Set Insert |
| Magnets | 3mm Neodymium (for frame lid latch) |
| Polymer adhesive |