prototype evaluation

I have completed making a small self powered light. It is made of aluminum and it has got a small solar panel and 2 white led’s. The light is a box shape and it was cut out inside the cam machine. The cam machine is a computer aided machine that cuts out most material in the form of a sheet. The cam machine cut out 2 parts to the box. One part of in the shape of a plus and the other part was the bottom of the box. With the first part that’s shaped like a plus, I had to drill 4 holes in the top using a drill press. Two holes are placed on the outside for the 2 white led’s to come through, and two holes are placed in the center of the top panel for the solar panels wires. Once I have drilled the holes out, I had to bend the sides of the box up. The box was bent on a metal bender. A metal bender can bend sheet metal. I folded up 2 sides to 90°. One problem that I encountered was folding the other 2 sides upwards. I could only bend them up to about 45°. To resolve this problem, I had to bend the metal by hand. Once the box was bent, I then needed to make up 4 brackets to hold the sides of the box a lot stronger. I got some scrap aluminum and scribed out my brackets. I cut them out in the metal guilitine and marked where I need to drill the holes for the rivets to go through. Once I marked where the holes were going to go, I drilled the holes out. Another problem I came across was that I had to drill the holes in another place of the bracket on the other side to make sure that when the brackets are riveted in, they won’t clash with each other. Once I had drilled the holes in the bracket, I then had to bend them 90°. After I had bended my 4 brackets, they were finished. So the next step was to drill holes in the box using the bracket itself as a template. 16 holes were drilled in total using a cordless drill. Then I riveted the brackets to the box using 3.2milimeter rivets. The top and sides of the box were complete. I was now up to the stage where I have to bend and drill the bottom plate for the box. The bottom plate was in the shape of a square with 4 small tabs coming out from each side. The first job was to scribe on the four tabs where the drill holes are going to be. Once this was complete, I then had to drill out the holes and bend the four tabs upwards. The tabs fitted around the side of the box. Another problem was that the tabs were not long enough to fit on the outside of the box, so it had to be forced to fit using a wooden hammer. After this was complete, the back plate fitted tightly. After that, I had to use the back plate as a template to drill holes into the box where the holes in the tabs were. The next step was to put screws through the holes that I had just drilled out. I had finished making the box, so the next thing to do was to modify the circuit. I had to desolder a warehouse circuit out of another solar garden lamp I had pulled apart previously. I removed the battery snap, the solar panel and the white led. I soldered on 2 new white led’s in parallel and then heat shrinked the terminals and soldered a new battery snap and new wires for the solar panel. Once I had done this, I then glued the circuit to the aluminum box along with the battery snap. Then, I pushed the led’s through the 2 holes in the box and glued them in place. Then I screwed the back plate on to the box. I also pushed the 2 wires for the solar panel up through the 2 holes in the centre of the box. Once this was complete, I soldered the solar panel. Then I glued the solar panel to the box leaving about 2 millimeters between the solar panel and the box to prevent a short circuit. The final step was to get some silicon sealant and put it around the solar panel to seal it up. My prototype was complete. I really like the size of the lamp and I like the industrial look about it. And I like the material chosen and also I am very happy because the light works. The one thing that I could do better next time is have the back plate cut bigger by 1 millimeter so that it can fit onto the box a lot more smoothly. Also I would like to have a three volt solar panel and 2 batteries in series so I can get the voltage of the circuit up to 3 volts for a brighter light output.