The frame of the LED matrix display we'll be building is constructed from the super useful extruded aluminum T-Slot. Extruded aluminum can be used to build nearly anything, it's very useful for prototypes or for building a rig to hold together equipment during the prototyping process.
The plan is to build a frame which holds the LED panels on the front, and the various electronics used to power and control the display on the back. Since the t-slot rails can be any length and has a channel running down their full length we can fasten the pieces to each other at 90-degree angles. We can also attach metal standoffs to the extrusions in order to hold our electronic components to the back, more on this later.
The LED panels I received from a distributor on Alibaba had a hole pattern that matched up well with 15mm square t-slot extrusion. This size is relatively small in the realm of extruded t-slot, but I did find the perfect size from OpenBeam, their 1515 series extruded aluminum was the exact size we need.
First, we need to make sure we have all the parts we need for our prototype display frame, here's a parts we need:
- 8x - 1515 OpenBeam, 450mm length
- 4x - 1515 OpenBeam (cut to 640mm length)
- 1 bag - M3 t-slot washers (be sure they fit 1515 t-slots)
- 1 bag - M3 6mm square headed hex screws
We're essentially making two large rectangular shapes (640mm x 480mm). When placed side-by-side they make up our super wide display. I originally planned to have the center hinged on the back so I could easily fold the display, but I decided to focus on getting everything working first, I'll focus on portability later (who's bringing this anywhere anyway?).
This could probably use a photo, I know, you'll have to use your imagination here as I forgot to take a photo of the rails all laid out, planning on coming back and adding more photos for this step, bug me on twitter if I haven't and you're interested in seeing more: @jpsilvashy
Screw the square headed M3 hex screws into each threaded hole in the LED panels. There are 6 per LED display (so 72 total, it's a little tedious I'll admit).
Leave the screws unscrewed with roughly a 2-3mm gap between the screw head and the plastic frame of the LED panels, this will allow the LED panel to slide onto the aluminum rails. I've found the best way to this and still have some friction between the LED panel and the extrusion is to screw in the hex screw a little further than necessary then as you're sliding the LED panels onto the extrusion, unscrew the screws just enough to slide onto the extrusion.
I'm not very happy about the rigidity of the unit once it's all assembled, the issue is that you can't screw the square headed screws into the washers tight enough while still being able to slide the screws along the slotted aluminium rail. This will make more sense later when we attach the LED panels.
Wiring the power and the components (coming soon)