Need a little bit of guidance.

hello, Im new with the whole making my own circuitry but I would like to get into it. Im going to start on something possibly difficult, Im not too sure what ill be getting myself into.

I am a Volunteer firefighter and we are aloud to have blue lighting to help us get to the seen faster and also to protect ourselves when on the side of the road. Seeing how every light setup I have seen is pretty much over priced I decided to build my own. I went to lowes and got 2 sets of 50 LED christmas lights and stripped them down to the LED. Thats all I have done so far haha.

what I want is 40-50 LED's on one side and 40-50 LED's on the other Flashing 3-4 flashes per second per side. This would be ran on my trucks 12 volt system. If anyone could give me some guidance I would greatly appreciate it.

The first thing you'll need to do is determine the voltage and current ratings of those LEDs. A lot of blue LEDs will have a forward voltage of 3.6 to 4.0 Volts. Max current a blue LED can handle (usually) is 20 or 30 milliAmps. The LEDs from the light string might have thes stats. Then again, they might not.

Are you willing to potentially ruin a coulpe to find out for certain? If so, find a 12V regulated source and a 270 Ohm resistor and we'll go from there...