It was so much fun building my first rechargeable solar light and besides I had 3 more no more working garden lights at my hand that I had to do something with them.
One might argue that I just changed the design but something else might be of interest for you and that is the arrangement of the LED's
Step 1: Tools and Materials
Tools and Materials:
An old solar garden light
Copper pipes and fittings (of course)
Soldering iron and electronic solder
Hot glue and/or 5 minute epoxy
Ruler, tape measure, compass and caliper
Drill press + drill bits
For details on the donor, wiring and schematics, please see Miss Betsy's Rechargeable Solar Nightlight!
Step 2: Preparing the Acrylic
From the dumpster behind the dealer I have lots of different pieces of acrylic. The 1 I used was about 3x0.75x0.3 inches. After cutting it to size, I smoothed the surfaces with different grades of sanding/emerald paper (150,240,400,600) and polished the piece on my drill press with a foam sponge attached. Watch out, acrylic gets hot very fast and starts to melt then!
For the same reason drill acrylic at low speeds, in this case after marking and predrilling with a 5mm drill bit. The LED's fit nice and snug.
Step 3: Preparing the Copper Pipe and Wiring the LED's
With the help of my Dremel, a cutting disk and a metal saw I cut a 7mm slit in the pipe and 'T' After filing two shallow grooves in the acrylic, it was gripped tight by the pipe.
Then I soldered the wires to the LED's and a first test was successful.
I like to test and retest the assembly after each step so that I can catch any malfunctions right away which saves me taking the whole thing apart..... (You know what I am talking about?)
Step 4: Holder for the Solar Cell
Two pieces of foam board serve as holder for the solar cell. They also allowed me to attach the copper pipe securely with hot glue. The 2 parts are glued together and the edge is covered with electrical tape.
Step 5: Inserting the Rest of the Parts
I needed to hide the PCB along with the LDR, battery and switch. Luckily the PCB fitted exactly inside a 1/2" copper pipe; for the LDR I had to drill a hole and seal it with epoxy, ditto for the SPST switch. Add the rechargeable 800mAh AAA battery and we are basically done.
Step 6: Finishing Up
Once everything works to your satisfaction, secure each joint with a dab of glue to prevent the light from disassembling itself ;p
The 3 LED's give enough light to show your way in the night or illuminate the pages of a book.