Pinewood derby cars

[atgcpaul]

My almost 4 year old is in Awana at my parents' church. They're doing the Pinewood derby in about a month. We bought the $5 kit from them which includes a roughed out car shape, plastic wheels, axles that press into a groove cut in the body, and decals.

I've never done this before. Seems some people go nuts and buy upgraded wheels and axles. I can feel the wheels wobble on the axles, but all that stuff just seems like cheating. However, I'm not opposed to adding some graphite--which is allowed--or trying to reduce that wobble.

Anyway, her only input is that she wants it pink and purple. We started flipping through car websites but she isn't interested in the body shape at all--just pink and purple (which she'll paint). What can I reasonably expect an almost 4 year old to accomplish? Obviously if there's any major body shaping to be done, Daddy's going to do it with the band saw or sander/OSS. She can do final sanding for painting and then apply decals.

I'm trying really hard not to be a helicopter parent.

[gsmittle]

Firstly, THANK YOU for not doing the entire project for her!

Do polish the axles with 800-2000 grit sandpaper. We (my sons and I) had pretty good success chucking the axles in a Dremel and running it about half speed. It helps to lightly sand the wheels, too.

Try to get the weight as close to the limit without going over as you can. We discovered that the weight and polished axles (assuming the wheels are aligned) affected speed more than body shape, etc.

Please keep in mind that we didn't do any formal testing, just observing results at derbies.

g.

[Stytooner]

Well, if you come up with a design you might like, I have a cnc mill here not doing anything, but standing by just in case. It is my first home made 80/20 mill.
Seems like heresy, but I will offer it and my 3D cad skills and machine time if you want something non main stream. Something that might be hard to whittle. I used to build wooden toys and models and I was in the Boy Scouts as a kid. Always been intrigued and fascinated with the dedication and passion for that particular hobby. I understand if you want to do it yourself.

[capncarl]

I think that the project is designed to give the child some daddy time. Most kids do not really care if they win, just have a good time and get to eat some hot dogs with their friends. They would be better off if the cars were to be made out of clay or some material that the child could shape with their hands without having to use dangerous tools. There is a man in a community near us that specializies in building pinewood derby cars to order. He knows how to push everything right up to the edge of the rules. This is wrong. Kinda like doing your childs homework or science project. Nothing is learned by the child.

[Black wallnut]

I think that the project is designed to give the child some daddy time. Most kids do not really care if they win, just have a good time and get to eat some hot dogs with their friends. They would be better off if the cars were to be made out of clay or some material that the child could shape with their hands without having to use dangerous tools. There is a man in a community near us that specializies in building pinewood derby cars to order. He knows how to push everything right up to the edge of the rules. This is wrong. Kinda like doing your childs homework or science project. Nothing is learned by the child.

Pinewood derby started when Cub Scouts started in 2nd grade back when boys were learning to whittle at that age, often with adult supervision. IIRC popular mechanics ran a kids column that had projects only requiring a pocket knife. The Woodright Shop did an episode on this once, fascinating stuff. Having been a Cub Scout leader and dad my observation has been that shape does not play any part in performance at all. Max weight, axle polish and graphite is what wins. I am not sure who makes the Awana kits. If the wheels are made from the same molds as the BSA ones then look for a mold number on the wheels. Higher numbers I believe are better and the low numbers not as much due to molds being old and worn. If you can sort wheels so all 4 match sometimes that is better as well.

The reason I'm quoting capncarl is that it is my view that even a fork is a dangerous tool and yet kids learn to use them without injury. Our society seems to be drifting towards one of fear of anything that could be considered dangerous, when often people hurt themselves more on items not considered dangerous like staircases, slip, trip and fall hazards. Meanwhile I have been carrying a pocktknife since I was in 4th grade. Sure I cut myself a few times but I've injured myself much worse as an adult with tools. Most people can be taught to use nearly anything safely. Paper should be banned to prevent paper cuts...... last time I was in Costco I moved a slip sheet off the toilet paper and cut myself.

[LCHIEN]

probably at 4 the most they can get out of a project is time together with Dad. Maybe joy in getting to choose the colors and basic design. and having thepleasure of having something come together in which she made the choices.

THere is quite a thrill to winning either a appearance contest or the speed contest.

I always thought there should be separate contests for the kids and fathers in which the fathers could go all out either engineering-wise of tool-wise.

having built one (my son built one with some supervision and I built one) I found there was no adult in the troop that was interested in my idea.

Anyway, its hard to really make one go fast given the rules of having to use the wheels and axles from the official kit.

In my experience, aero shape has little to do with it.
wheel alignment is important, I built a 8 foot ramp with lengths of doorstop on it just to test rolling improvements side by side.
some people claim having the fourth wheel higher so it doesn't actually roll makes it go fast - the slots provided with the kit are usually quite perpendicular to the body, if drilling your own a drill press is helpful. Taking the wheels off and on a lot makes them loose and hard to keep aligned.
Weight distribution, shaping the wheels so they have a narrow crown to reduce friction (Illegal in most rules) polishing nails, replacing oval, rough, undersized nails with precision rod (illegal since most rules require using the supplied nails) all can help.

In the end its best not to overthink it.

[Bill in Buena Park]

A lot of good replies already, especially the axle polishing and graphite. My kids have done this with AWANA as well, and I did the basic shaping (until they were old enough to reach the bandsaw - under supervision), they did the sanding and painting. We worked together to polish axles. Some years they won, others not, but they had fun, they remember each car, and that's the point. kids that seemed to have the most fun made the wildest looking cars, and some none aerodynamic versions would surprisingly beat the more aero versions.

[capncarl]

I wasn't pointing out that 4 year olds shouldn't be using knives, my kids got their frist .22 rifles at that age, just that a lot of kids this age, given that this is a sunday school type project, might not be able to handle an exacto knife. Getting the kids out from under the parents thumb promotes their creativity. Personally I would like to see them use a material that they could form better and see what they came up with. We all know that a 6 inch long piece of pine is not the easiest thing to make look like a race car.
capncarl

[Black wallnut]

Fair enough, I misread the 4 yo part or did not retain that fact by the time I read your reply. FWIW I think the first PWD kits had Idaho white pine in them which is just a tad harder than balsa wood. No where near as hard as SYP.

[cwsmith]

Our Pinewood Derby days were long ago when my little guy was in Cub Scouts... he's now 43!

I do believe it's all about "Daddy time" as some have put it and I do remember it well. Back then, IIRC we bought the car through the cub pack and went over to visit a neighbor who had a son my Jason's age. He had already conducted his other three boys through the tradition and he offered some good advice and hints, and also forewarned us that THIS was a lot more about fatherly winning with too many of the Dad's.

So, the two of us went to a local hobby store and he picked out some Testor's spray paint, two colors... red and blue. My little guy had zip manual dexterity back then, and though his reading skills were very high, he couldn't print anything legibly... still can't! So I figured he could handle a spray can easy enough. I did the masking though.

No tools to speak of, so we used a rasp and a sanding block and most of the time, it was both our hands on the rasp as I helped to shape the body. We 'emeried' the axle nails and I used model railroad graphite on the wheels and mounted them with him watching that part of it. Together we made a little plastic windshield from some scrap, he used his mother's hair dryer and I bent the plastic to fit the notch in the body we made.

We came in about 10th place, but it was fun and we thought we had the best looking car there. BUT, you should have seen how skilled some of the father's were. A few of them barely let their boy even touch their cars. Then of course there were more than a few cars which looked very much like their Dad's enjoyed a football game or something else, during the project time. (Oh, the winner... my little guy said it was last year's winner, repainted.)

The exercise should be fun, and it was for us. It's also a lesson in sportsmanship, and perhaps too, getting a little understanding of human nature.

CWS

[Brian G]

I'm going to be simple and focus on one thing:

What can I reasonably expect an almost 4 year old to accomplish?

A pink and purple car, like she wanted.

[LCHIEN]

Brian is absolutely right, try and make it look as much like she describes it to you so that she thinks you have delivered her vision exactly.

she will have the experience of having a vision come to fruition and you will have had the satisfaction of making a 4-year-old happy.

[greencat]

It's been a long time but the simplest improvement we made was truing the wheels. Mount them in a drill and use sandpaper to take out any run out.

Sent from my SCH-I545 using Tapatalk 2

[Pappy]

At 4 she obviously is not going to be able to do much on the construction of the car, but keep her involved as much as possible. The memories will stay with her much longer than who won.

My boys did everything on their cars in Cubs that did not involve power tools. Neither won, but they both finished in the top 10 every year. The youngest still has a couple of his cars.

We had a "Dad's Derby" one year. It was a 'no holds barred' race with the only limitation being the official weight. Amazing how close the fit and finish was between some of the Dad's cars and those of their sons.

[iceman61]

As most have said polish those axles! Also smooth out the back head of the nail. It will rub against the wheel and it is usually rough there and will act like a brake when it rubs against the wheel.

Get the weight as close to the max weight as possible without going over. It is easier to add a little weight at check in than to take weight off. Your weight should be concentrated around the back axle. Center of gravity should be 3/4" in front of the back axle. This is achieved with weight just in front of & just behind rear axle. Some rules say nothing about "all four wheels must touch track". This means you can have one front wheel raise so it doesn't touch the track (three wheeler). This reduces rolling friction and makes the car faster.

We found that a flat 1/4" car body was faster. try to cant your axles just a little so that when the car starts rolling the wheels move to the outside head of the axle and not into the car body. My son always won 1st place in all pack races and in the top 2 in district races only getting beat out by "internet bought cars".

There is some great help if you read through this forum:

http://www.derbytalk.com/

Good Luck!