Simple Extruded Aluminum Frame for LED Panels
Introduction: Simple Extruded Aluminum Frame for LED Panels
We really like to use LED panels for making clocks, game timers and information boards. Our family has used a Raspberry Pi based "Weasley Clock" for the last five years. In a one minute cycle, it displays the time, weather, school information, and local train schedule. It will inform us of any delays or stoppages in the train through a scrolling message. It can also display alerts for internet outages. They have a Halloween mode that allows them to fill the room with a ghostly green glow or a fire effect. Our clocks are based on Raspberry Pi 3's and the Adafruit RGB LED hat. They would not have been possible without <PERSON> amazing libraries. ( https://github.com/hzeller/rpi-rgb-led-matrix )
With the introduction of the Adafruit Matrix Portal, we built a couple of smaller ones. Over the next year, we will try and migrate some of the code for the "Weasley Clock" over to them. For building a single application, they are great, and the kids program python.
That brings us back to the purpose for this Instructable, the point of which is due to my dear wife. She took one look at the Raspberry Pi, the Matrix Panels, power supplies, wires, lots of wires and said "No way is that monstrosity going on my kitchen counter." It has to look nice. Fortunately, she as a very generous definition of what "looking nice" entails.
Using some leftover extruded aluminum and steel bars, we have come up with a simple and easy to adjust design that looks nice, and with the addition of a piece of 35mm din rail, will be well organized and tidy. We present it here to you.
Step 1: Figuring Out What You Want to Build.
There are a lot of choices here, and you need to figure out some things before you start. What are you going to use the display for? A display device such as a clock, message board, or timer? A light source for special effects or background lighting? A chess clock or scoreboard that needs buttons? Something else?
First, how many panels do you want to use, what density and what pitch? Where is the panel going to be viewed from? How far away will the viewer be? How many LEDs will be lit at a time? Go do some research, Adafruit has some excellent tutorials.
The most common configuration we built used 128x32 LEDs. Both of those were made with two panels of 64x32. The biggest one we made was 128x128 LEDs. It was made with four 64x64 panels. 769
This is overkill for most projects, unless you are displaying train schedules or using LED Lab ( https://apps.apple.com/us/app/l-e-d-lab/id8320421...) with the most excellent pixelpusher. ( https://github.com/hzeller/rpi-matrix-pixelpusher ) . We would suggest starting with one panel of 64x32 to get started. (If you expand it later, you only have to replace two of the extrusions in the basic design.)
The next thing to consider is the pitch of the panels you want to use. Pitch is how close the LEDs are to each other on the panel. The smaller the pitch, the closer the LEDs, and the smaller the size of the panel. The smallest pitch we use is 2mm, the biggest is 6mm. The 2mm is great for desktop displays and the 6mm is good for when the display is on the other side of the room. Again, go do your research.
The second to the last thing to consider is what processor is going to drive the display. There are a lot of choices ranging from Arduino's, Adafruit Feathers, Raspberry Pi's and Adafruit's Matrix Portal. Go do your research and remember, the processor is the easiest (and cheapest) part to swap out.
Lastly the biggest thing to consider is the power supply. GO Do Your Research. We size the power supplies by figuring out the current required to light up every LED on the panel and then adding a fudge factor. (Remember that halloween mode.) The power supplies can run up to 80 amps at 5V. If you are not going to drive the panels that hard, you might get away with a smaller supply. GO DO YOUR RESEARCH.
Once you have decided what you wanted to build, and have the parts in hand, it is time to get started with the measuring. ( It as also best to the software that you intend to run, up and tested. )
This is a minor warning, depending on where you get your parts from there can be subtle differences in what the data sheet says and what is shipped to you. 635