We will build a modular and scalable LED Display made from Club Mate bottles and boxes.
The first prototype will consist of 840 bottles in an array of 6x7 boxes (30x28 Pixel) .
To build it, we have to do many (at least 840) repetitions of monotonous working steps. Because we do not like tedious work it will be necessary to develop efficient production processes and tools.
The Idea is to use illuminated bottles as pixels, more precise the bottoms of the bottles. To use the bottles as pixels, we will wrap them into aluminium foil and attach one RGB or RGBW into each bottleneck. When you put the prapared bottles back to their boxes and tilt the boxes by 90 degree, you will look at an array of 4x5 bottle bottoms. If you prepare more than one box, you can arrange them to a display.
The idea for this kind of display is not new, during this project we will develop, document and share our own approach.
After working hard for two month, we got the display working for the first time. The mechanical part was tedious but easy done.
The electronic part was a bit complicated. We ran into problems with the control of the pixels, because we used WS2812 from different suppliers. We used LEDs on white PCBs and LEDs on black PCBs. It seems that there is a issue with the timing, we found out that we are not the only ones which ran into trouble with using the two types of LEDs together: https://www.geekabit.nl/projects/wedding-gift-sprite/ (section testing and debugging). We fixed the problem by using only the WS2812 mounted on white PCBs.
The power supply is not finished, for the moment we are using four ATX power supplies.
Also the mechanical structure is not finished. For now we attached the single boxes to a wooden structure with cable ties:
So, the display is not finished but to watch the working display it is very impressive if you stand in front of it.
After cleaning the bottles and removing the labels, we have to wrap them in aluminium foil ...840 times...
First we have to cut 840 sheets of foil. We decided to use aluminium foil with a width of 30cm, which is enough to wrap the foil about 1.4 times around the bottle. If you use foil with a larger width, you will waste a lot of foil or, more important, you have to make two cuts instead of one for every sheet.
We identified that the lenght of each sheet should be around 23cm. Because we do not have to mess with tight tolerances, it is possible to use a very simple tool to cut several sheets at once.
The idea is to wrap several layers of aluminium foil around a core with a perimeter of 23cm and cut all layers at once.
To realize this idea we used two pices of MDF with a thickness of 3mm and a height of 109mm. The width of the MDF parts should be at least the width of the aluminium foil. We used pices with a width 450mm.
First, join the two pices by making a hinge with some kind of tape on the long edge of the pices.
Then, add some kind of spacer inside the tool. We used thin wire which was taped to one MDF part.
To produce the sheets, place the aluminium coil on a roller. We used a plastic box and a pice of tube. Clamp the start of the coil with the tool (this is the reason for using two times 3mm MDF with a hinge instead of a single 6mm MDF pice). Now you can start to wind the aluminium foil around the tool.
After several windings (up to 15 are really good feasible) cut the aluminium foil.
Voila! Several sheets with a lenght of nearly 23cm at once. Use the foil to wrap the bottles and secure the wrapped foil with some kind of adhesive tape (not shown in the pictures).
We learned that one cutting-person can easily supply the aluminium sheets for two wrapping-persons just in time.
I tried to create a simple as possible solution to attach LEDs (presoldered strings) into bottlenecks. If you do not use presoldered LED-strings, there might be less complicated ways to mount the LEDs into the bottles.
1. Mark the Dout side of the LED PCB (optional):
2. Feed the LED through the base plate:
3. Place the PCB on the wedge, the Dout side must face to the two little fins:
and bend the wires around the wedge
Insert the wedge into the baseplate:
Now push on the cap and lock the wedge with a bolt (for thermoplastics 3x10). Note the form of the baseplate, it matches to the counterpart in one direction only!
Finally, snap the socket to the sodabottle. Optional fasten the cap wit a 4.8mm cable tie.