Foo - Pinewood Derby Question

OK - I know there are some of you leaders/parents out there. I have a question for you.

How are cars brought to a stop on the track your boys race their cars on? We set up towels at the end for cars to plow into, but I know there has to be a better technique out there.

On our track the tire grooves get deeper so the cars end up with their wheels in the air. This part of the track is covered in a foam material

http://i144.photobucket.com/albums/r162/jsharr/Pinewood/100_1007.jpg

http://i144.photobucket.com/albums/r162/jsharr/Pinewood/100_1001.jpg

If you have a wooden track, you can make a finish section out of wood. We made our return track and used a router to do this. At the finish end, we just set the bit deeper to achieve the same effect. That is the two lane return track in the back ground.

http://i144.photobucket.com/albums/r162/jsharr/Pinewood/100_1005.jpg

OK - I know there are some of you leaders/parents out there. I have a question for you.

How are cars brought to a stop on the track your boys race their cars on? We set up towels at the end for cars to plow into, but I know there has to be a better technique out there.

I can't remember how they stopped our cars! But I do remember the high tech computerized timing device, which registers each cars time on a computer! My oldest boy won several races. I think I made like 5th or 6th place one year.

Our first car only travelled on three wheels, and still made I think like 3rd place!

One of the fathers built an addition onto the end of our track. Basically extending the lanes about 2.5 to 3 feet. The extension created a gradual incline to the lanes so that the wheels of the cars were lifted off of the track. Some thin foam rubber weatherstrip or 1 inch sand belts (can't remember which worked best) was applied to the surface of the incline for friction.

Worked in 90% of the cases. Of course we still had plenty of foam rubber surrounding the finish area.

Zorro, our pack's track is in my garage, I can get measurement or snap some pics off the wooden finish section if you need.

It would look cool if they plowed through water, or flaming oil.
.
BTW, do you have to use pine wood?
.

Yep, it's a kit - pine block, axles, wheels.

Ours is just like jsharr's. Those pics show it perfectly.

Yep, it's a kit - pine block, axles, wheels.
Is every block of pine the exact same density?
.

Is every block of pine the exact same density?
.

When you are finished building your car, it can't weight over a certain amount. I can't remember what the weight limit is. Usually people carve the block of wood into various shapes, then add weights to the bottom. I've seen some people who just kept the block of wood the original rectangle shape though.

We always just folded a blanket up and had a couple kids kneel on it at the end of the track, so the cars would stick under it or bounce off.

Is every block of pine the exact same density?
.

Nope, they are all different, but the complete kit out of the box is around 4 oz. Most pack's have a weight limit of 5 oz. and the scouts that want to go fast are within a few hundreths of an ounce of the max weight. Many of the boys in our pack were at 5.00 ounces.

When I was in cub scounts, the track they used was just like jsharr's. I won first place in my pack, my first year as a webelo. :cool:

Edit: Is it weird that I want to do pinewood derby again, now?

BTW, check the pre-cut axle grooves in the kit. Many times we found they were not square to the block. Can't get your car to go in a straight line if the wheels aren't square!

If the rules allow it, get a drill press and drill axle holes. The jig for this is a decent investment if you do not have a drill press.

When I was in cub scounts, the track they used was just like jsharr's. I won first place in my pack, my first year as a webelo. :cool:

Edit: Is it weird that I want to do pinewood derby again, now?

I am Dremel-ing my second son's car today. It's really quite funny around here - the first time dads really get in to it. One of the Pack Mothers had a great comment - "This is great, we should have one for the boys too." She said this with good humor. By the time my older son was a webelo he was doing the whole car himself. And that's the year he won first place.

My son's first year we put very little work into the car. We didn't really know what we were doing either. Despite dropping his car, breaking a wheel off, and many of the weights, he finished first among his age group.

Put more work into the cars after that (with my second son also). Never did as well again!

Polish your axles. Polish your wheel hubs inside. Put your wheels and axles in zip lock baggie and add graphite and shake them a few minutes a day. Drill your axle holes. Get weight to 5 oz. Space your wheels close to car to minimize wobble.

With regard to polishing axles. Apply graphite to the axles and burnish them with an electric drill. The heated graphite becomes even more slick after cooling. This only needs to been done once to the axles. NEVER touch or apply graphite again to the axles. My buddies kid took 1st place out of 1500 kids. When they saw competitors applying fresh graphite to the axles they knew they had won that race.

I am Dremel-ing my second son's car today. It's really quite funny around here - the first time dads really get in to it. One of the Pack Mothers had a great comment - "This is great, we should have one for the boys too." She said this with good humor. By the time my older son was a webelo he was doing the whole car himself. And that's the year he won first place.

I have never done this, but I had heard that especially for some specific groups is is more of a competition for the dads than the kids... It seems like it would be great father/son fun!

I have never done this, but I had heard that especially for some specific groups is is more of a competition for the dads than the kids... It seems like it would be great father/son fun!

It is in the later years. In the first few years of cub scouts, the kids aren't quite old enough appreciate all the tedious work that goes into it (sanding the thing seemed like torture to me when I was that age). By the first year of Webelos (9 or 10 years old, maybe?), I was better able to get excited about it.

Pinewood can be a bit challenging for the tiger and bear cubs (1st and 2nd graders). They need some help cutting out the body.

But they can be set loose on the paint. It is pretty funny to see some of their designs.

The older scouts 3rd-5th grades, really take ownership of their cars.

It is easy to discern the kid built cars from the dad built cars.

The nice part is that aesthetics have no effect on speed. My first grader polished his axles and we hammered them into the holes we drilled and made sure his car weighed 5 ounces and he took first place.

I helped even less this year, and he still took third place.

The nice part is that aesthetics have no effect on speed. My first grader polished his axles and we hammered them into the holes we drilled and made sure his car weighed 5 ounces and he took first place.

It wouldn't surprise me if the shape of the car made a difference, even if the quality of the paint doesn't. If I had it to do again, I'd do a low airfoil-ish design.

Aerodymanics does not matter at this level. I have read studies on this and seen it first hand. One of our fastest cars this year was called "the block". It was the uncut, untouched stock block and the father and son spent their time in my garage polishing axles and truing wheels.

Wheel alignment is critical. The car needs to run straight.

Getting the weight to max is also crucial. Potential energy. If the rules say 5 oz. max, then make sure the car is as close to 5 oz as possible.

Weight placement is also key. You need to get the weight low and in the back of the car

I won first place as a commander for show, never won anything for a race. I made a boat and dyed it blue then did all the finish stuff. It raced like a boat on land. :)

Zorro, our pack's track is in my garage, I can get measurement or snap some pics off the wooden finish section if you need.

I think the concept it pretty simple to apply. Will let you know if get stuck.

Thanks everyone.

Pinewood derby was so much fun.

When I got to middle school, my technology class did CO2 powered cars. Those were awesome... and fast.