I Need Help Like Right Now!!

The simplest thing for you to do if you want to use the Lego car, is to attach a propeller and rubber band from a model plane and have it blow towards the back therefore pushing the car forward.

 

no rear axle, right? Just two wheels on little prongs on the back of the car.

That makes wrapping the axle with a rubber band anchored to the front of the car kind of tough. Ya know, wind up the back wheels, let 'er go! That certainly would have been the easiest way to make it.

Without an axle, the only way to get 'er moving would be some kind of coil spring on the rear wheel that you could build some tension with, and when you release the car, the spring would unwind. Might be able to fashion that from a small spring around the house, but if it's only on one wheel, no guarantee it'll go straight, at all.

MAybe a very small fan, like a personal cooing fan could be mounted on the back. Flip on the switch, you have an air car.

Other than that, wihtout an axle, you are up the creek without a paddle.

DM

 

i build model airplanes, from rubber powered to control line, so my rubber power experience is large, id put a spruce spar on the car glue it on there good with some epoxy fashion any supports you need from wood and epoxy them as well, then go on down to the hobby shop pick you up a winder 5x1 is decent to aid in the winding, and get the motor rubber, place a hook on the far nose end of your car, the propeller on the back tie a knot in the rubber wind it 300 winds or so and let her rip, pick up some rubber lube too so you dont break your band your first time out and dont overwind, maybe practice with it a bit just wind it hold it in your hand to get an idea of the amount of winds you need. also make sure you balance the prop. trust me you will get alot of thrust depending on the propeller you choose a 6 inch prop should do the trick so id start there pick a nice medium pitch or maybe even get a variety of props to alter your cars speed. also if you get crazy a few stabalizer fins here and there can only help. you could also do the prop on the front and do a puller prop instead of pusher but that would be up to you.

p.s. dont whack your finger it hurts like hell and wind it the right direction so you dont look crazy having it slam backwards into yourself and bystanders. trust me when i say a good rubber powered motor can be quite terrifying and you cant turn it off it has to unwind itself and I for one wouldnt want to be the one to try to grab it so deffintly test your motor and decide how much to wind it,

how far does this thing have to travel ? or is it purly concept ? big space to run it small? long and narrow running space, is it a track ? large wide gymnasium ? if its large and wide you could put a fixed rudder so the car would make large circles instead of just going straight youd have to calculate your rudder angle though and know your floor space size. 300 winds with a lazy prop could probly get your car moving for 30 seconds or more maybe even a minute.

take plenty of pics of your car

 

Throw a couple of Estes model rocket "D" engines on there and light 'em up.

That should get it moving.

 

How about a little solar panel powering an electric motor ?

 

What makes a stationary object start to move? Energy!

Since energy can be neither created nor destroyed, only changed in form, where does that energy come from? Stored energy, like a battery or a spring, or heat energy, like burning fuel, or transfered energy, like wind power or a mouse running in a wheel. It won't move without a source of energy.

Your challenge is to provide that source, harness it, and use it for your purpose. We would need to know the rules of the project in order to give you more hints. You should figure it out yourself anyway.

 

Been there done that (13+ years ago!)

Go to radio shack. Get a little tiny motor that will run on a single 1.5V "double A" (AA) battery. Modify the indy car to run off of this. Can you add a little plastic gear to the drive axle? If so, add that gear. You can transfer the power from the motor to this regular gear via a "worm gear". Mount the engine longitundally, mount the worm gear in line with the engine shaft, fit the worm gear over the regular gear on the axle, and you have power.

You can make this happen tonight if radio shack is still open.

Good luck!

 

great post!

 

screw dat... you need some "M" motors...

 

What about doing it somehow with magnets? Look up "Maglev Train" and you'll get the idea. I made one for my daughter on a very small scale when we she was learning about different science projects. It's tedious and probablly more time consuming because you have to build a track.
Admittedly though, I like the propeller idea by Gershwin!

JIM

 

the above mentioned solar panel idea is a sound one too, head on down to the dollar store and get like 15 of those crap solar calculators, pull out all the solar panels, solder all the leads together, + and - then buy the crap turn in reverse rc car and pull the motor out of it, or buy one if they have one, then all you need is a good flood light bulb and an extension cord and some sort of light fixuture, hook it all up, the gearing was mentioned, heck the rc car probly had lots of these bits in there, then go ahead and place your solar panels on it, and shine our light should get enough juice to move the car , if its not enough run more panels, or brighter light, id go with 150 watt bulb right off the batt too.

 

Prius motor. Maybe you can get a tax write-off for this.

 

Get started sooner in the semester.

Procrastination is a waste of time.

 

Are you one of those guys who will beat up the class nerd for showing up with a carbon fiber molded, radio controlled, hydrogen scramjet powered hovercar?

I guess putting a metal rod inside and then using a bulk tape eraser to pull it wouldn't qualify as "under its own power". How about a couple of party balloons for "rocket" power?

But I'd guess that the point is to think up something unconventional -- like converting the bearing friction as a gyro winds down. A science demonstrator would probably get more points from a science teacher than an off-the-shelf electric.

Google for "tesla turbine". Got some old CDs or an old HD and some compressed air? (e.g. those party balloons.) You might not have time (starting late) to make it work well, but if you have the science paper to back up a barely moving design, that may score better than a fast moving machine powered by "some kind of magic thingie" from the store.

 

i dunno, i agree with those who said that you should have started earlier, but i guess if i was in your situation i would modify my design to put in a rear axle and do the rubber band wind up thing to power it. otherwise, the comment above with the party baloons would work

 

Give it a jet engine by using a CO2 cartridge. (not sure how you'd puncture the end though)
(I liked the Estes rocket engine idea the best)

Maybe a Vinegar + baking soda engine ?

(I guess you could also do some sort of vinegar + water engine, then you could call it a Duschenberg)

 

Maybe in today's schools, even bothering to try to do homework is "above average".