We wanted to make a costume-prop for Halloween that resembles the Neuralizer from Men in Black. However, we wanted to make sure that it has super simple, working, electronics so that it can be whipped together at the last minute! Therefore, we designed this 3D model which could fit a capacitor based flash/blitz circuit running on a normal 9 Volt battery. The flash itself is a 10 Watt LED (Voltage drop: 12V, max current 900mA), but could easily be replaced by a more common LED (just make sure to change the value of the current limiting resistor). The specs of an LED will depend on the color it emits, but 2V and 20mA seems to be a decent choice of parameters in many cases (read more here: https://electronicsclub.info/leds.htm). To calculate the size you need for a current limiting resistor, use a LED calculator and find specs in the LED datasheet, or use the values I provided above: http://ledcalc.com/ . Keep in mind that if you switch out the battery with something other than 9V you will have to redo the current limiting resistor calculation. We believe that the circuit design we show here is the simplest possible capacitor based LED flash.
When the 3D design was done, we printed it out, sanded down the layer lines with a 80 grit sandpaper, then primed it with a cheap plastic filler (made for car bumpers - the exact brand shouldn't matter at all). We repeated this process until the finish was smooth and free of obvious holes. We then used a black primer paint on the parts that we wanted to stay black (near the LED opening in the lid), before assembling the electronics and gluing everything together. We used hot glue, but immediately regretted that decision because it cooled down too fast so it was impossible to tune the alignment of the pieces. We should have used a contact glue or an epoxy. When this was done, we primed the rest of the piece with black paint, then went on to do a few layers of silver, and finishing off with a clear coat to protect the paint.
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Open Source files:
Instructable: https://www.instructables.com/id/Worl...
Writeup: https://hackaday.io/project/168234-si...
3D files: https://www.printables.com/model/3440...
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Twitter: / appliedproc
Facebook: / appliedproc
Instagram: / appliedprocrastination
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Credits:
Intro/Theme song:
Nicklas Myhre: / myhre.nicklas
Music:
Funny Song from Bensound.com
Endless Motion from Bensound.com
Little Idea from Bensound.com
Sound Effect Mixing:
Eivind Rostad