Wednesday, March 11, 2009

Tuesday, March 10, 2009


Today was the today. The day where we tested our balloon car for our assignment. Surprisingly Mr.P only said " It has to reach 5 metres " to ensure our car exceeds 3 metres, which was the real requirement to recieve the minimun of 35/50 or 70%. Luckly, our car passed the finished line ! :) :) ... unfortunetly it did not go as far or as fast as we thought. We had to do many adjustments before our turn to race, we changed the position of the wheels, took off the alluminum foil off the wheels, and inserted rubber that would go around the wheels to reduce friction. The one thing that helped us was the rubber on the wheels ( WHY DIDNT WE THINK OF THIS EARLIER? haha), it made the car go straight. We actually didnt add the rubber to ALL the wheels because we just had one, but surely if we had two more, it would help our car a lot. We think our 4th design would of done better, even though that car did turn more than our car right now, it went very fast, but it's OK ! Therefore if we had another chance to do this assignment we would of stuck to our 4th design and would of changed the wheels, maybe to something more durable and steady ( real car wheels or something large yet not too heavy ).
We greatly enjoyed this ballooncar assignment.

Now we're done the car, it's time for the report; we're gonna do 150% better on our report, to make up for race day . But overall, We think we did the best we can do, compromising our ideas together to make the most decent XPLOSION ballon car :) :)

To summarize the race:
Trial ONE - I blew the ballooncar, hoping that it would reach the 3 metre mark. Mr.P says "GO" ... FAIL ! My hand got caught inbetween ... well with the ballooncar. SOOO then again, I had to blow into the car, ... here goes nothing. After, Mr.P repeats himself, and our car MOVES ... NOT ONLY WAS OUR CAR MOVING, IT WAS TRAVELLING IN A STRAIGHT LINE, and, it reached the 3 metre mark ! We were so happy ! =)

Trial TWO: Before this trial, we attached another balloon. Reason being, the balloon had so much saliva in it ! ( I know, NASTY !). I then blew the balloon and let it go for the second trial. The ballooncar didnt even move =( But atleast we made it on the first run! Why didnt it move ? The car did not move because we attached the balloon to the car with very tight tape. This ensured the air to escape the balloon slower and with less power and air to push the car.

The End.

Monday, March 9, 2009


Materials we used :
alluminum foil->it reduced the turning of the car... a bit. This was a last minute thing, I could not find anything else to add to the car =(.
knex wheels->the best wheels we could find, plus the weight wasnt so bad =)
BBQ sticks->We wanted to be original =) Its light, and easy to work with
bristle board. WHY? For decoration.
straw-> it let the air esacpe the balloon slower, enabling it to move the car.
rubberband-> to attach the balloon to the straw
gluegun/glue/tape -> Obvious reasons :P
balloon-> used for the "gas" of the car. ( the air escaping the ballon car)

X-PLOSION BALLONCAR ! We fixed our car, and now it goes in a straight line ... (most of the time, still not perfect, but we tried our best =) ) !! YAY.Tomorrow is race day, and we hope our car does well !

Sunday, March 8, 2009


AND SO WE CHANGED OUR IDEA.. WELL, we're trying something different, because our car wasnt travelling in a straight line because of the balloon, it was because of the CAR ! the car's point at the top was not straight therefore making the car travel towards the left. AND SO, trying to fix that problem, we sketched a new car, using the same material. BUT if this car doesnt work we will stick to the other design and redue the whole car, making sure the measurements are correct and accurate

Saturday, March 7, 2009


We just decided to change our idea.. well a BIT, we discovered that our balloon car was a BIT TOO heavy, so... here are the changes :
1. took out one wheel, to make the ballon car have THREE wheels.
2. you know that red part you see in the picture of our recent ballooncar ? The one that is attaching the wheels to the car? We changed those knex parts to bbq sticks ! AND OBVIOUSLY it reduced the weight of the car by a lot :)

Thursday, March 5, 2009

The Problem is ...

the problem is the freedom of the ballon; if the ballon starts moving the car tends to move in zigzags. To fix this problem ...
a ) insert the balloon in net and attach net onto car
b ) create a fence around ballon to prevent it from moving

We tried both, but havent decided on which one is better ... * still in discussion

concusion - we did not do any of the ideas, we just taped the balloon securely to the car.

Wednesday, March 4, 2009

Combination of both cars

We put parts of our cars together to make a ballon car that works very well !
BUT the only problem is making it travel in a constant direction ; to make it travel in a straight line.
materials we used :
knex wheels with some other knex material like the sticks, BBQ sticks, straw, string, and cant forget the balloon !

P.S. this is the 4th car we SHOULD have raced with for race day.

Update on Idea One

So I've decided to totally change my whole idea since my last idea didn't work too well. So I made the body of my car out of bbq sticks and the wheels with sewing material ( the rolls ). Here is a picture of it ...

BUT this did not work either due to the wheels. So .. I think the biggest challenge is to find better wheels.