Monday, May 28, 2012

Building the $100 night light, Part V

Finishing the "Building the $100 night light" series, Part V focuses on final assembly...

With all the design work done, it was time for final assembly.  Unfortunately, I did not take enough photos of the work in progress, but did capture one right before the lid was attached.



All of the components fit well on the PCB, with only one major flaw.  The large capacitor in upper middle part of the board was too tall for the Hammond enclosure.  Live and learn - for the next hobby project, I will need to pay more attention to available heights.  Rather than attempting to attach wires onto the leads and glue the cap somewhere else in the case, I settled for soldering it high on the PCB (lots of the leads above the board) and folding it over -- not pretty, but it works.

For the LEDs, I soldered wires onto the leads and crimped connectors on the other ends to attach the components to the PCB.  While searching for the appropriate drill bits to use for the 5mm and 10mm LEDs (I do not have a metric set), I came across the following site which had a convenient table.   For the 5mm I used a 3/16" bit, and for the 10mm I used a 3/8" bit.  Each was a little to snug, but angling the drill a bit while drilling gave enough gap to fit the LEDs properly.

Finally, the PCB was attached with 4-40 screws to the enclosure, and the lid attached.  See the below picture for the final night light.


Where the project cost a ridiculous amount compared to a store bought item, it was a great educational project and had just enough complexity to hold my lab assistant's interest.

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