Big news...

[gpraceman]

BK, is this event limited to your Council, or might there be an open race for scouts / Scouters outside to Council to take a spin down the Centennial 1000? If so, will there be a fee to participate (and how much)? Could be an excellent fundraising opportunity...

Maybe also do an Outlaw race with entry fee. Imagine some outlaw cars screaming down that track?

Also, with the World's Longest Track, you should have the world record speed for a Pinewood Derby Car. Something else to look into and play up.

[dna1990]

I am not the physics resource, but my thought is that the Mall-track (forget the name, but you know the one we have all seen pics of, they launch from second story)...that has a MUCH steeper drop and should have top-end speeds much more than the Akron hill.

Just guessing by our hill, a 5oz car seems unlikely to have enough inertia built up to sustain over the longer flatter section at the bottom. Might not even finish, more less be going 'fast'.

SBD cars themselves at 240lbs are only around 32mph at the finish.


A big gust of wind, could indeed derail a 5oz car.

Having 1000' of track/channel is alot of places for debris and alignment issues, joints, etc. Are we talking wood? I can't imagine the $ for that much aluminum.

Keep us posted. And if an invitational system gets setup for scouts or non-scouts to mail-in entries.

[FatSebastian]

my thought is that the Mall-track (forget the name, but you know the one we have all seen pics of, they launch from second story)...that has a MUCH steeper drop and should have top-end speeds much more than the Akron hill.

Granted that it is a simplification, but the equation for maximum speed is primarily governed by the relative height of the starting point. The slope of the drop should not be a very significant factor in the maximum speed obtained; however, a steeper slope allows a vehicle to reach its top speed in a shorter amount of time. Understanding that a 50' drop is like have the starting gate placed on top of a five-story tower, the top-end speeds at Akron hill should be noticeably greater than the Mall-track (assuming that the drop is really 50').

Just guessing by our hill, a 5oz car seems unlikely to have enough inertia built up to sustain over the longer flatter section at the bottom. Might not even finish, more less be going 'fast'.

Perhaps, although Stan seemed to disagree. My own intuition would be that a carefully built car would cross the finish line at 1000' with plenty of speed to spare. (At least the simulation seemed to affirm that.)

SBD cars themselves at 240lbs are only around 32mph at the finish.

The physics would be the same whether we are talking about SBD or PWD; to draw a comparison I believe what matters most are the differences in the cross-sectional area/mass ratio, and the differences in the mass moment of inertial of wheels relative to the total vehicle mass. I personally don't know enough about SBD specifications to make the comparison, but trust your assessment that woodcars would be at a disadvantage racing against a SBD car (now there's a spectacle!)

[gpraceman]

I believe that you guys are referring to the 125ft track used at the Indiana State Museum race.

This has got me wondering. So, bad_karma_2805a1, is 1000ft the total length of track, including the stop section or is that just the start to finish measurement? A long stop section will be needed with that much speed going, so maybe that is being factored into the 1000ft. Either that or some type of capture system that will not damage the cars and stop them in a much shorter distance. Now, that would be an interesting engineering feat.

[FatSebastian]

I believe that you guys are referring to the 125ft track used at the Indiana State Museum race.

Perhaps so.

Either that or some type of capture system that will not damage the cars and stop them in a much shorter distance. Now, that would be an interesting engineering feat.

I think a stop section that incorporates an upward ramp (e.g., mirroring the start section) might have promise at slowing the cars down enough to capture them with minimal damage.

[Stan Pope]

Just guessing by our hill, a 5oz car seems unlikely to have enough inertia built up to sustain over the longer flatter section at the bottom. Might not even finish, more less be going 'fast'.

Perhaps, although Stan seemed to disagree. My own intuition would be that a carefully built car would cross the finish line at 1000' with plenty of speed to spare. (At least the simulation seemed to affirm that.)

The latter part of the track is still sloped. Even a gentle slope should keep the car going unless it had nasty-bad alignment.

[bad_karma_2805a1]

Wow...few days away from the forum and this thread took off. So let me see if I can answer a few questions.

Um first to answers F.S.'s question, we are planning on opening it to anyone and everyone. Yes there will be a fee for racing it, because we plan on having t-shirts and stickers for everyone who participates. We are working on what the fees will be but yes there will be one and we will keep it to a minimum. I am not looking to make a profit, just see some little cars race down a long track.

As far as classes go, gpraceman wanted to know about an Outlaw class. Well currently there is a plan for two classes, stock class(BSA rules apply) and Unlimited/Outlaw/RWYB class (we think it will have two rules; car should be within BSA specs for size not weight and no hazardous items, example rocket engines.) But that still needs to be hammered out.

The distance of the track and the finish area are all still being worked out. I talked to All American today and they are actually getting me a copy of the blue prints. The rough numbers from the top to the very end of the track are 1,500 to 1,800 feet. Since they moved the starting line down the hill, the actual distance has kind of fallen from memory. I should know soon what we are looking at, then we can all run the numbers...lol.

Which leads to another thought from a post...yes I would think we might be able to have the fastest pwd car. But who knows, it all comes down to the drop and how they run I guess.

And I think my final comment is this...F.S. I think you named it "The Centennial 1000" has a very nice ring to it.

I will keep you all posted as more information comes in.

[FatSebastian]

I am not looking to make a profit, just see some little cars race down a long track.

Certainly you'll want to to cover your expenses; a track / event this large is liable to be expensive. Souvenirs of some sort (e.g., T-shirts) seems like a great idea. (How about vest patches?)

Well currently there is a plan for two classes, stock class(BSA rules apply) and Unlimited/Outlaw/RWYB class...

When the opportunity presents itself, could you elaborate on what will be meant by stock "BSA rules"? For example, the rules in the box are different than, say, the Cub Scout Grand Prix Pinewood Derby Guidebook, which IIRC, illustrates illegal tread modifications that the box rules don't address. Also, many local units consider use of the slots or standard wheelbase as "BSA stock", although that restriction has never been published by the BSA to my knowledge. Etc. ...

[bad_karma_2805a1]

Well got the call back from the track company and we will be running a two lane track. I had hoped we would be able to run a four lane one, but to make sure we get the distance we want...two lanes is what we are going with. Thinking of the scale size, it seems like a drag race between to cars on the Salt Flats...lol. Should know more soon about the hill, just wanted to keep you all posted.

[bad_karma_2805a1]

So 1000 feet should be more then do-able on the hill. I talked to Derby Downs and they gave me a few numbers you all can crunch.

Total distance from top of the track to the end of it, 1,500 feet.
Incline at their starting point, 11%.

I am going to try and walk the hill this week and get some heights from the very top to and then like every 20 or 30 feet down the hill. Once I have them I will let you know.

Something to think about, the starting gates for the soap box cars causes a slight rise in the track. So this will have to be dealt with to keep cars from flying I think.

[gpraceman]

Something to think about, the starting gates for the soap box cars causes a slight rise in the track. So this will have to be dealt with to keep cars from flying I think.

Maybe make the finish of the track be the finish line of the race course. So, start the track downhill from the SBD start gates.

[sporty]

You might use boards to keep the track raised up higher until just past the start gate, then let it start to drop.

I would start from the top, the old starting point at the track. Not sure there is no where near enough drop if you started from the gates.

Theres enough runout area after the finish line for a good stop section or added track.


Then also there is a enough good seats before the finish line, if you needed to shorten the track before the finish line. that still gives a grand and pleasant view of the finish.

Sporty

[Stan Pope]

Since the effect of "drop" (slope) is a concern as to whether cars can finish the whole run, you can evaluate this by trying cars on your test board. How many inches of drop along the length of the test board are required for the car to run the board with a minimal nudge to get the car started?

If it takes, for instance, 2 inches of drop along a 4 foot test board, extrapolate that to inches needed for a 1000 foot track: 2 inches X (1000 feet / 4 feet) = 500 inches or 42 feet of drop from start to finish. I bet that most of your cars can accelerate on an even gentler slope.

[bad_karma_2805a1]

Morning all, well just wanted to check in and give you all an update on the project. So we are starting to get sponsors together and the committee will have it's first meeting this week. I can tell you that everything has been rolling right along. I was out of town for two weeks and I personally feel a little behind but at this point we are still on schedule for August. Talk to you all soon with the classes and the chance of mail in cars.

[dna1990]

We are still very interested, so do keep us posted.