Unlimited Pinewood Derby

[JoeyGee]

In addition to the standard Pinewood Derby this year for my son's pack, we are doing an unlimited parents' race. Basically, use a standard PWD kit built car and add whatever you want to it.

I need ideas. I had thought of using compressed air (for an unlimited raingutter regatta) but abandoned that because I could not figure out a on/off mechanism.

Anyone have any good ideas for propulsion? I think the plastic wheels may cause a traction problem with whatever I come up with...

[woodinville guy]

well the front will sit against a peg. somehow that dropping needs to be the trigger. who cares about the off part :-)

[iceman61]

we call that "open class" or "outlaw class"
I have seen videos (youtube) on the net where a remote controlled fan was attached to the car. Pretty fast, but IIRC the fan & wireless remote were in the neighborhood of $40. Some scoutmasters build these just to get the boys excited about the race since there is alot of sitting around.

[iceman61]

Never saw the compressed air thing until you mentioned it up check this out:

http://www.youtube.com/watch?v=pEWTf...ture=fvwp&NR=1

[os1kne]

very slick!

[sailor55330]

I'm sure it would be DQ'd, but could you use a model rocket engine? I'm sure there could be a spring loaded trigger device that completes a circuit that engages a 9v battery for ignition.

My guess is that violent explosions and risk of fire would probably not be allowed, however, it would be fun and give the opportunity to work on a wing shape to provide downforce.

[Shep]

What about something simpler like a rubber band somhow wound up, that would release it's energy when the gate drops?

[sparkeyjames]

How about one of those small CO2 canisters, like the ones used in pellet guns, with some sort of remote controlled electric valve.
Definitely need wings for down force.


Sometimes unlimited really does not mean unlimited.