Elastic Band Car

[scientist314]

Note: Sorry about my previous topic, it was a little..odd.

 

Any help or input will be appreciated. :singer:

 

So for my Physics project I need to build a rubber band/ elastic car that will carry some weight (contest) over one meter.

 

What I've thought of is to have two rectangular wooden sticks placed horizontally as a basic frame, and to have a thin board on top of the two sticks to support/connect them and hold the weights. This way, it's pretty light so it should be able to carry the excess weight, right?

 

What I'm not sure of is if one rubber band will be effective enough. I understand you need to anchor one end of the band on the drive axle and one end on another spot somewhere on the car, and then wind it up and release it.

 

I don't think one band will be strong enough to carry significant weight? I've thought of using more than one rubber band (e.g. tie two together), but I have a feeling this will interfere with the first rubber band, or something unexpected will happen (such as one getting loose and then interfering with the wheels).

 

I've attempted something similar to this before with a mousetrap car, but what I'm most worried about is if the rubber band will have enough stored energy to move the car and the weights.

 

Any input appreciated. THANKS!

[scientist314]

Please. Any help would be appreciated.

 

I figured since I'm forced to use a wooden axle, to cut a piece of aluminum to cover the space where the axle and the frame meet to reduce friction.

 

Using CD wheels, I'm not sure how I can fit them onto the axles without them being loose/stable. I tried using spacers/washers, but to no avail. I thought of using popsicle sticks, but popsicle sticks aren't thick enough to cover my 3/8" axle.

 

Again, any help appreciated!

[scientist314]

Okay I have basically figured out everything except for how to attach the CD wheel to the 3/8" axle and to figure out some sort of bearings.

 

For bearings, I tried using some pieces cut off of a pop can, but i still heard some scratchy nose..

 

Any ideas?

[InfiniteNow]

Are you allowed to use silicone lubricant?

[scientist314]

I suppose so, but where would I get that, and wouldn't it be expensive?

 

The major problem I have left with dealing to is the wheel. I tried using washers and gluing them onto my wooden axle, but it was really loose. Popsicle sticks wouldn't work either as the axle was too thick.

[InfiniteNow]

This may sound too simple, but have you tried smaller washers? :)

[scientist314]

Yeah, I have. :)

 

My axles are 3/8". I tried using 3/8" washers but they was actually aobut 2-3mm of extra diameter space. And then I tried 5/16" washers but they were JUST too small... :)

 

Right now I'm thinking about using cushion pins to secure the end of the axle, and then just secure the other end with rolled up paper, but I have a fear that the pins will crack my axle.