Importance of balance point

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Speedster
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Importance of balance point

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In our workshops we stress the Importance of the balance point. In a test run in 2011, this car left the track at High Speed. The heat from the friction skidding across the floor caused the car to burst into flames. Fortunately, no one was injured. After the scouts see what horrendous damage an improper balance point can do they are very careful.
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Noskills
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Re: Importance of balance point

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:jawdrop:
No way!
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Stan Pope
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Re: Importance of balance point

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Good one! :bigups:
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FatSebastian
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Re: Importance of balance point

Post by FatSebastian »

Speedster wrote:After the scouts see what horrendous damage an improper balance point can do they are very careful.
I wonder how many Scouts would attempt an improper balance point just to see if they could cause horrendous damage!
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Re: Importance of balance point

Post by BallBoy »

Interesting picture. I find the brief story quite hard to believe. Is there more to it that you can share? What is the car made of? I have thrown a lot of wood on a lot of campfires and I don't ever recall the wood warping and melting as a result. Wood usually retains its shape and simply catches fire. What was the floor made out of that would produce significant enough friction on a car going 8 MPH that it would reach temperatures greater than 500* F before the car slowed to a stop? In starting campfires using friction methods (i.e. without matches) it takes at least 15 seconds and a tremendous amount of elbow grease to even start smoking, let alone get combustion.

I agree that balance point is important, but I doubt that catastrophic failure is a plausible result of improper balance.
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Re: Importance of balance point

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Ballboy, you're teasing me like I do the young scouts. The car was made from a BSA kit. I built the car, cut it to get a wrecked shape, and glued it back together. I then final shaped it using auto body filler (Bondo). I refinished it with automotive Basecoat/Clearcoat paint so it would have a shiny paint job, striped it, and let it dry. I held the wheels over the stove and pressed them on a metal pan to get flat tires. I then held the front of the car over the flame and it did the black damage you see. The ripples in the front of the car already were there when I shaped the Bondo. The young scouts get big eyes when I'm telling them the story. Their parents just stand there and smile. When I'm all finished with my story I tell them the truth.
We also have a discussion on what will get a car disqualified regarding illegal wheels under our District's rules.
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Noskills
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Re: Importance of balance point

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Haaa
Reminds me of Apacalego where at the Lego conventions they create elaborate destruction scenes. Pretty cool. Would recommend going to the Lego Brickfair with the scouts sometime.
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Re: Importance of balance point

Post by 5kidsracing »

Those are awesome Speedster.
For my "Pinewood Story" go to: http://5kidsracing.webs.com/index.htm
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Re: Importance of balance point

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We had a car take 1st place yesterday in one of the dens. I was sitting at the finish line. The car pulled what looked like 1/4" wheelies all the way down the track. We have a very smooth circular arc wood track and the car managed to stay on the track. The car was a basic wedge using the short end for the front and it balanced directly over the rear axle. The 1st track the scouts race on at District is a "Best" track and the cars travel 29'. Do you think this car can survive the "Best" track, or later, a 40' Freedom track? No one wants to see this scouts feelings hurt nor have his car ruin another boys car. Since it is a basic wedge should I recommend the Team build another car? Strangely enough, he had another son that also took 1st place, wedge design, CM of 1", but used the long end for the front. That car ran fine.
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Re: Importance of balance point

Post by TXDerbyDad »

FatSebastian wrote:
Speedster wrote:After the scouts see what horrendous damage an improper balance point can do they are very careful.
I wonder how many Scouts would attempt an improper balance point just to see if they could cause horrendous damage!
Mine would just be looking for the fire starter to skip the middle man. :rofl:
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Re: Importance of balance point

Post by whodathunkit »

After futher review of the photos.

The Inspectors have decided that the cause of the fire damage.. was not due to improper balancing of the car!

Rather that it has been pre-determined as a stageing problem..Caused by the monster truck OutLaw wheels.

From when the car left the track at high speed skidding across the floor onto the red carpet ..
That it was (Static Shock) that caused this...( Alcohol preped axle )Funny Car to burst into flames.
Resulting in the catostrophic melt down!

Speedster,
It's a Cool looking car!

Whoda.
What type of automobile can be spelled the same forwards & backwards?
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