Our 2012 Cars

Show off your cool vehicle designs and track burning speedsters!
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Topspin.D
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Our 2012 Cars

Post by Topspin.D » Sun Jun 17, 2012 7:08 pm

This is the car my son, my father, and I built for his Tiger year. Turns out a car that we thought might be competitive was pretty good and won the pack. It's based on a design by David Meade.

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This is the car I build for me and other son for the sibling race. It was rushed (the axel/wheel prep weren't very good) and has a design flaw that made it unstable at the district track. The rear spoiler is a 3 oz. weight. The theory was that the higher the weight the farther it had to fall coming down the hill (longer boost), which was true, but when it transitioned to the flat it wobbled a lot and lost speed going back and forth.

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I would give my son's car about a 6 out 10 and the blue car about a 5 out of 10 for preparation.

Both were 3 wheelers but neither were set up as rail riders and there was no canting. Also no bore prep (other than graphite). We didn't shave wheels either.

I've bought the rest of the tools I need to do much better prep next year. My son and I didn't like loosing at districts (because of 1 bad run) and are determined to have a more consistent car next year.

A few more pictures of the two cars.
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whodathunkit
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Re: Our 2012 Cars

Post by whodathunkit » Sun Jun 17, 2012 9:05 pm

GO GO GO!

But what ever you do.. Watch out for differnt starting pen hights with that blue car.
Good thing for a little duck tape. ;)


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

Topspin.D
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Re: Our 2012 Cars

Post by Topspin.D » Sun Jun 17, 2012 11:19 pm

Yep. We race on a wooden track with a manual start at the pack, but at districts they use a pretty nice aluminium track. I sent a few emails to organizers asking about pin heights before I built this car. Didn't want to risk it on the black car (my son's car), but on the sibbling/parent car... I figured we'd try it out.

The blue car is fast of the start due to weight and quick start, but transitions horribly.



Speedster
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Re: Our 2012 Cars

Post by Speedster » Mon Jun 18, 2012 5:10 am

I think it has been determined "Cheater Bars" are no advantage and may well be a disadvantage. Weight high "on the car" is the reverse of what you stated. The car starts on a hill. Experts put the weight as low in the car as possible which will put the weight as high up the circular arc as you can possibly get it. If you are going for all out speed, "Think thin to win". I think Sporty might have said that. If he didn't say it his cars surely show it. I hope this helps. Good Luck.



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Noskills
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Re: Our 2012 Cars

Post by Noskills » Thu Jun 21, 2012 7:52 pm

Thanks for sharing the photos and experience

Noskills


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Shawn Stebleton
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Re: Our 2012 Cars

Post by Shawn Stebleton » Mon Dec 24, 2012 3:10 pm

Nice car.
Topspin.D wrote:The theory was that the higher the weight the farther it had to fall coming down the hill (longer boost), which was true, ...
Actually, the lower the weight the farther it falls. I created a page with that info in it and have it somewhere at home. I've never posted it online. Maybe after the holidays I'll get a chance to find it and get it posted.

Basically, think along the lines of "a lower weight is lifted up higher" when on the starting grid compared to on the flat, and the raised weight is tilted down some at the starting grid. Picture a car with one weight above the car and another below the car. Now, rotate it midway between the two weights about 30 degrees to simulate being on the starting grid. You've just raised the lower weight and lowered the raised weight. When the car gets to the bottom, it has had to raise the higher weight but the lower weight gets lowered even more. The lower weight has more potential energy.

If wanting to make a car with a raised wing, I usually suggest using a craft stick (tongue depressor). They're common and inexpensive. I also suggest to the scout to make it level to minimize wind resistance, instead of angled.

The craft sticks are also good at extending the front of the car after chopping off the rear so the rear axles can be as far back as possible. If designed as a front wing, it looks cool.


Shawn

rpcarpe
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Re: Our 2012 Cars

Post by rpcarpe » Wed Jan 16, 2013 11:19 am

Thanks for the stories and lessons learned.
Also on the elevated wing weight, it makes your car top heavy and therefore wobbly.

Good luck on the next batch!


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