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My Son is building Pinewood derby cars and he wants to set one up to run flashing L.E.Ds. Answered

2 head lights 2 tail lights and 2 red and blue over head lights. This is to resemble police car and it has to stay in the size of the car and weight Width: - 2-3/4" Length - 7" Width between wheels - 1-3/4" Weight - Not over 5 Ounces THANKS any help would be great !!!!?


Keep it simple: just use ready-made blinking LEDs for the flashers, regular LEDs for the head and tail lights, and a small lithium battery to power each set. Less complexity means fewer things can go wrong.

This post looks a little old but my son built a great looking derby car using  lights from pinewoodlights.com

The headlights would be the easiest part as you could just wire two leds in series/parallel (depending on resistors available and voltage of battery) with a button cell. The lights on top could be accomplished with two blinkm smart leds. They are ideal for this project as they are pretty tiny and you can load up a particular light sequence with an arduino. The sequence (say, blinking red and blue lights) will then run whenever 5 V is applied to the led and will run independantly of the arduino. The best part is that the platform is made for artists/people with little to no programming knowledge so it is incredibly easy to get into. That said I'm sure there is an easier way. I'm pretty sure they make Leds that automatically flash so I would check sparkfun or a similar site for parts.

To save on weight and size, you might also want to do some free-form soldering instead of using proto board. You can also use small 3v coin cell batteries, which won't last long (how long, I don't know), but are really tiny.

To run that many lights to blink, your best bet would probably be to use a microprocessor. I use and like the Arduino setup because it's easy to learn, but I don't think it would fit inside the size constraints of your car (and if it did, it would sit on top and make it look very electronic!) You could pretty easily wire a circuit that would just have constant light -- flashing is a bit tougher, but I'm sure if anybody can think of a good way to do it, it's the folks around here!