0.8 Hours -
With some more supplies arriving from Aircraft Spruce, I decided it was time to start wiring the wingtip LEDs. I decided to use thermal epoxy, rather than thermal paste, to sink the LEDs to the aluminum back plate. I did this because I didn’t want the LEDs moving around while I tried to solder them. If I was a bit better at soldering and figuring out wire lengths, the paste probably would be fine. The downside of the epoxy is that the LEDs are going to be incredibly difficult to remove if I ever need to replace one.
To glue the LEDs, I mixed up a small portion of epoxy and spread it on the back of three LEDs. I then positioned the LEDs on the back plate and screwed the mirrored plexi down on top of the LEDs. The holes in the mirrored plexi positioned the LEDs and held them in place until the epoxy set. I then repeated this with the other three LEDs.
Once the epoxy was set, I laid out a wiring schematic and pulled out some wire (22 gauge tefzel). For each piece of wire, I cut it to length by holding it in position and snipping off the appropriate length with some side-cutters. I then stripped and tinned each end. Finally, I soldered it into position on the LEDs and moved on to the next wire. When I was done, I had six LEDs wired in two parallel series of three. My soldering technique still needs some work, but the connections seem solid…they just don’t look very pretty.
Finally, I used some test leads to connect my Buckpuck driver to the LEDs and flipped the switch on my power supply. This was the first time I had six LEDs on at the same time, and I saw spots for the next half hour. One of these days, I’ll remember not to look directly at the super-bright, high-powered, LEDs. Seeing all six turn on sure was cool though!
This schematic shows how I wired the LEDs. I may still try a resistor instead of the driver.
The red LEDs have been glued to the back plate and soldered together with 22 gauge wire. It isn't pretty, but they work.
