Thanks for the advice,I think Ive got a better idea of how to go ahead. Ive looked at some leaf micro switches for the finishing line.What worries me about a mechanical trip switch is that the cars are hand carved out of pine,and the wheels nailed on therefore the height from wheel on track to body ...

Maybe this ?
http://www.adafruit.com/products/439

Just had a quick look at sensors


http://littlebirdelectronics.com/produc ... ght-sensor

So ,the car passes over the sensor,which is hooked into the Pi.In principle would something like this work ?

The mechanics of the track are easy enough,I work in the furniture industry programming CNC routers,so I can make up some pretty fancy stuff. Here's my last project

http://www.youtube.com/watch?v=Zw_b6UIgIuQ

Hi Dougie There will be four lanes.I was thinking microswitch on the start line when the pins drop to trigger the timer.There wont be a display on the track as per the video,I would like the finishing times to be displayed on a screen that that Pi is hooked into. The finishing line sensors,there wou...

Hey Guys Ive got a project in mind that would utlilise my Pi,I was wondering if someone could point me in the right direction as I dont have the first clue where to start. I am constructing a pinewood derby racetrack ,similar to the one in this video http://www.youtube.com/watch?v=tC5qRw7QhLA I woul...

Hey there ! I'm Gary , expat Scotsman living in Australia. I am about to purchase my first Pi, not having the first clue about Linux,but looking forward to getting to grips with it.I played around with basic as a kid,and program CNC machines for a living,so hoping to pick it up quickly. One of the m...