I've read the previous posts on the forums, good stuff, and have been experimenting with a combination of cool white and blue leds. Everything looks good so far. I am going to use the triggering set-up that stan2004 suggested in a previous post titled "Subway track spark simulation".
In watching the video that he also posted, I've decided that I would like to add to the idea one more touch, to somehow "delay" proceedings so that the spark looks more random.
Wondering from stan2004 or the other electronics experts what the easiest way to possibly do this might be? Something that would allow the leds to have a delay before they would be able to light up again. In this way, the "spark" wouldn't happen with every wheel hitting the trigger.
Thanks guys and have a nice 4th of July!