Its Pinewood Derby time....

[Manipulator]

This is the second year for my son in the cub scouts and its time for the ole Pinewood Derby. Last year we were doing great up until the last few runs and got edged out and beat. We did take second. Was unable to go to the finals as we were going on vacation the week it was held. <br /><br />So come on dads, let’s hear those secrets for making this car fly down the track. Our district has pretty tight rules for the district finals but the pack race is pretty much open for some modification. No cut tires but I beveled them last year. Some others did some tricky stuff too. Lets just say the pack rules are the same as district but loosely followed until the obvious. <br /><br />Last year I used "liquid Gold" furniture polish as the lubricate on the axles. I remember when I was in cub scouts this what dad used and it worked great. I also took second myself but got smoked at the district event. Here is the problem. The car is real fast for the first half of the runs and then slows down as the lubercate evaporates. This year I am thinking of trying something new.

 

[toomanyboats]

Re: Its Pinewood Derby time....

three year winner here,(my son I mean)I helped Used Grafite on wheels,sanded and beveled wheels,Weight in the front,Its been 6 years

 

[Pony]

Re: Its Pinewood Derby time....

Well I am not a dad......but I used to be a scout, and did pretty well in the pinewood derby. Took 1st once and 2nd twice (last three of my boy scout years).<br /><br />1. I always used lots graphite powder on the nails (axels)<br /><br />2. Always went right up to the weight limit, and usually got there with a small weight bar than you could imbed into the bottom of the car (towards the front ) You just break tiny pieces off until your car is the correct weight.

 

[Manipulator]

Re: Its Pinewood Derby time....

I have a digital scale and we get the weight right on the money. As far as where to put the weight remains a question. I have heard you want it way up in back as it helps push the car down the track but you also run the risk of the car popping a wheely and flying off the track. I wasn’t physics major so who knows. I believe it has something to do with the center of gravity. With the center of gravity higher, it will help accelerate the car down the incline of the track.

 

[Pony]

Re: Its Pinewood Derby time....

Well my thinking is if all the cars weigh the same.....their accelerations are all identical down the ramp regardless of where you put the weight.<br /><br /><br />If I remember correctly the top of the ramp where the cars start isnt at the same incline as the main track......You want you car to get to the incline the quickest, the front gets over the "hump" first and will accelerate quicker at that point IMHO

 

[Bob_VT]

Re: Its Pinewood Derby time....

Hmmm mount the axles in a dremel or drill and polish the surface ever so slightly, use dry graphite to lube, the weights are not lead (that would be poison but I have seen people melt lead to fit the shape desired to cut back on the bulk.<br /><br />A good fancy paint job is required with a clear coat!

 

[alden135]

Re: Its Pinewood Derby time....

I am always impressed the most with the cars that perform the worst.<br /><br />It's always obvious which Dads are competing with the 10 year olds and which boys actually did most of it themselves.<br /><br />They should just call it what it has become- a "Dad's Derby"<br /><br />Sure makes the boys who follow the rules feel like crap.<br /><br />Alden the Scoutmaster

 

[CN Spots]

Re: Its Pinewood Derby time....

My wife's Girl Scout troop borrowed the local Boy Scout's track and equipment last year so that the girl's could hold their own race. There was a seperate category for "grown-up" cars if the parents wanted to enter. There was a "Best Brakes" award for the cars that didn't make it to the finish line.<br /><br />According to all the derby websites, the graphite is the best lube. We didn't have any so we used Quantum Hot Sauce (reel oil) on the axles. I didn't have a scale so when we weighed it at the track the official said we were gonna get clobbered unless the car was heavier. I went out to the truck and found a couple of tungsten worm weights, drilled some holes and hammered them in. We didn't win, but we had fun building the project and I have some memories of my daughter that are more valuable than any trophy. <br /><br />spots

 

[wildbill59]

Re: Its Pinewood Derby time....

Rem Dri Lube w/ Teflon<br /><br />Spin the axles and wheels in a drill a lot

 

[RPJS]

Re: Its Pinewood Derby time....

If I am right in thinking you are talking about what I would call A Gokart or Boxcar, then there are 2 things that will make them go faster, these are weight and friction.<br /><br />The more weight the slower they accelerate but they will attain faster speeds going down the ramp, I gather there is a weight restriction to the cars so you may need to look at making the rider a little heavier.<br /><br />As for friction you need to look at three things.<br /><br />1 Axle lube and smothness<br />2 wheel width and allignment<br />3 Arodynamics<br /><br />Axle lube has been covered in previous posts, as for wheel thickness the narrower the better, a small contact point has less friction, wheel allignment is very important and is probably the thing that gets missed by most people, make sure that all the wheels are running true the slightest bit of toe in or out will slow you down dramaticly. As for arodynamics think bobsled.

 

[OLDSPUD]

Re: Its Pinewood Derby time....

This is a sure thing.<br /><br />winderby.com<br /><br />I have won every time I have made a car (about 10 times.) The folks in my neighborhood got so sick of it they started changing the rules (running cars backwards ect.) I still won.<br /><br />Just follow the instructions detailed in the "how to build book", it is written on a cub scout reading level.<br /><br />You can't lose. Use the speed axles and wheels, and use the pre shaped car.<br /><br />I usually let my kid on nephews shape and paint the cars, then I put the weight, wheels and axles on. put it in a box until you race it.<br /><br />I usually build it to weigh 4.9 oz so they can't think I'm cheating.<br /><br />You want it to run on three wheels, amd make sure it runs straight.<br /><br />Spud

 

[wildbill59]

Re: Its Pinewood Derby time....

The nails that are used for axles have some "flash" left on them just below the head. Take a small file and take off this flash, smooth with 320 sandpaper

 

[Manipulator]

Re: Its Pinewood Derby time....

Yeah I agree it should be called the "Dad's Derby". Thing is, my son was 6 last year and had no idea what to do. I helped him as much as I could but he was just too young to understand how to use the tools to make the car. I tried to help but ended up taking over. I understand the whole point is for father and son to bond together and accomplish the feat together. So I gave my son some of my MotorTrend magazines and a few Car and Drivers to take a look at cars. I told him to pick one and that would be the one we would try to build. He picked a Corvette. That's my boy! So I carved it and he helped sand it. I bought stickers and he put them on the car. I essentially did most all the work. Yes, we had the coolest looking car. We painted it red and then shot it with clear coat and he added flames (stickers).<br /><br />This year he will learn how to use the tools and I will guide him. I will do the wheels and axles and install them. I will do the tricks with the drill and polish the axles. I will bevel them like the "speed axles" you can buy. Thing is, I have to be careful as the district judges can get real tough and disqualify the car. I know of the three wheel trick but they would flag it for sure. <br /><br />I remember in my pack a kid's dad shaved the wheels down to where they were riding on a tiny bit of tread in the center. He smoked all of us but at districts they flagged him and he had to change the wheels. Needless to say his car sucked after that.

 

[ufm82]

Re: Its Pinewood Derby time....

The weight should be towards the rear and as high as possible- that way it stays on the inclined section of the ramp as long as possible and gets you a bit more speed. The last derby my son and I ran in was so close that the time were all between 10 and 10.5 seconds and there were 45 cars in the derby! We took 1st in his pack and 7th in districts. We were beaten by less than .1 of a second by the top 6 cars. We're talking hundreds of a second here! The wedge is still the best design. That winderby.com site and a couple others will give you the scoop on how to build a winning car. <br /><br /> UFM82

 

[BOBPELL]

Re: Its Pinewood Derby time....

Always came in 1st or 2nd. in a fairly large troop with my sons. BSA do not allow altering the wheels but if your troops says OK then take them to someone who can put them on a lathe. <br />Other than the wheels do ALL the following.<br />1. The "axels" they use are basically nails - on the back side of the head (which rubs against the wheels)are burs from the manufacture. You have to look close to see them. Gently push each one thru a piece of sandpaper and spin them while gently pulling to remove the high spots. <br />Make sure they are straight, some come bent a bit.<br />2. Add sufficient weight to bring it right up to the allowable limit - put the weight behind the front axel. Too far forward and the *** end <br />wobbles.<br /><br />3. When you insert the axels DO NOT push them in too far in (friction) or too far out (wheel wobble).<br /><br />4. THE SINGLE MOST IMPORTANT - following the above, find a smooth surface and be sure it rolls TOTALLY STRAIGHT by giving it a push.<br />Adjust the wheels to correct it. When you get the axels at just the correct angle without friction, glue them so they do not move. I used epoxy. <br /><br />5. Only graphite is permitted by BSA. Actually if you do the above it will fly down the ramp.<br /><br />6. After you get it all together and the way you want it, don't let your son play with it till after the race.<br /><br />Let me know how you make out - Good Luck!!

 

[coleman kayak1]

Re: Its Pinewood Derby time....

I was actually in 5 pinewood derby's. Went to finals all 5 years, but never was in the top 10. Here are a few tips:<br /><br />1. you want to be up to the weight limit, I found it went the fastest with the weight on the bottom, center of the car. I used Solid lead for fishing.<br /><br />2.Aerodynamics are key. 3/5 of my cars were xtra flat. Just be sure to leave enough space to put weight in.<br /><br />3. Always graphite the wheels/axiles. I would always let my wheels/axiles set in graphite for a year (make up after I finished racing).<br /><br />4. Always sand down the nails, they will be rough and cause friction if you do not.<br /><br />5. I found that a good paintjob helps. 1 year I went with just bare wood, and it was very bad performance. Another year I rattle-canned it and it did okay. But the best performace I ever got is when I purchased a small airbrush tool, though I have no idea where you would get one.<br /><br />I hope this helps, and enjoy the racing

 

[DJ]

Re: Its Pinewood Derby time....

I see all these "go fast" concoctions. Who's making the car, the kid or the dad? <br /><br />I did the PW Derby thing as a kid. My dad gave me hints, but he NEVER touched the car.<br /><br />I held the same rules with my sons.

 

[gewf631]

Re: Its Pinewood Derby time....

Originally posted by DJ:<br /> I see all these "go fast" concoctions. Who's making the car, the kid or the dad? <br /><br />I did the PW Derby thing as a kid. My dad gave me hints, but he NEVER touched the car.<br /><br />I held the same rules with my sons.

My son was 6 last year (first year, Tiger Scout), and although he helped, no way was I letting him do everything. At that age, he's not up to the challenge, nor, am I willing to be runnin' him to the ER.<br /><br />This year he'll do a lot more. Dad will still be there, but more for support and guidance.

 

[DJ]

Re: Its Pinewood Derby time....

My son was 6 last year (first year, Tiger Scout), and although he helped, no way was I letting him do everything. At that age, he's not up to the challenge, nor, am I willing to be runnin' him to the ER.<br />

Ed, you missed my point. Regardless of age, it's his deal-not yours.<br /><br />The winning or losing is "his/hers" not yours.<br /><br />You are the responsible parent that makes it safe, but YOU don't build it, in my book.<br /><br />When I was doing this with my sons, I saw cars that in no way could have been built by kids. They were "one off" originals built by crafty (living vicariously) parents.<br /><br />The "beauties" I built were my OWN creation. Win or lose.<br /><br />The same held true, with my sons. With a little "sage" advice-of course. <br /><br />This whole ideal is supposed to be about kids mastering the building process and enjoying the competition. Unfortunately, it has become about parents competing.<br /><br />Let the kids be kids and stay out of it. The same goes for team sports.

 

[gewf631]

Re: Its Pinewood Derby time....

Originally posted by DJ:<br />Let the kids be kids and stay out of it. The same goes for team sports.

DJ - I think we're on the same page, and yes, last year's car was far from being the most beautiful. But, this isn't a paper-and-glue operation, so he only did the work that wasn't too dangerous.<br /><br />I'm also a little league and soccer coach. We have practices, but they're mostly run like pickup games - a little work on the fundamentals, and use the game to build those skills. Push the kids too hard, and they'll burn-out. But they also have to learn the "right" way to catch/kick/throw/hit, and that's my job as "coach". Most of the other teams are similar, but there's a few...