PDA

View Full Version : Scouts - Pinewood Derby... anyone ?



Winston Wolfe
01-13-07, 09:03 PM
My son is 6 y.o. and in Scouts (currently a Tiger Scout). Next Saturday is our local "pinewood derby" race and I have just inspected the standard issue pinewood derby kit to build the "spec racer"....

I know this is a father\son activity to enjoy and bond over with my boy, but at the same time, I would like to have a respectible showing and maybe even a "Top 3" car....so with that in mind...:D

A few questions for the "race dads" out there who has been there \ done that...

-Has anyone participated in the derby before ?
-Is there a "better" way to do it other than instructions indicate?
-Do certain designs work better than others ?
-What are some of the keys to victory?

yeah, I know... what a way to take a perfectly innocent childhood activity and turn it into a competitive environment... but ya just know there are Dad's out there who have taken this thing to a WHOLE NEW LEVEL of competitiveness, and I just want to see if anyone has gone thru the process and can point me in a few of the right directions....

your assistance is greatly appreciated !

matthole
01-13-07, 09:08 PM
If you don't have a fully operational wind tunnel for this endeavor, you really need to rethink your priorities as a parent. How can you deny your precious child all the advantages? :shakehead

;)


Hire that cheater nascar guy, Chad. He should come up with something. :gomer:

Wheel-Nut
01-13-07, 09:43 PM
Do a google search.

http://www.maximum-velocity.com/

There needs to be a second derby held for just the dads.

Spicoli
01-13-07, 10:39 PM
why talk about pinewood? let's start talking carbon fiber and kevlar.:tony:

G.
01-13-07, 11:21 PM
Axles: All you need to know. Polish them sumabithes. Graphite the snot out of them.
I chuck them into a drill press and file, sand (with AlOx paper), then with 600 grit metal paper.
Then graphite. And more graphite.
Remember, if you win, you don't see the car again until the next round. They get impounded until the District Derby.

Aerodynamics don't mean much in the slow speeds that the cars run. Just don't put a wind sail on it.:p We won with a main-battle-tank last year.

Wheels, round. All 4 touching the table. Minimize the friction between the wheel hub and the painted car. I rub graphite into the paint to make it "shiney". I might try to taper the inside hubs this year to lessen the contact surface area. "But won't a cone-head bite even harder?" Dunno.

Get as close to the weight limit as possible. I assume it's 5 oz. Make it 5.00000 oz. Check on your Pack's scale. Bring tools to reduce weight to the track (a drill removes weight. Might want to bring a drillbit.).

Obvious stuff: Wheels point in the same direction, don't pull to one side, axles sealed into place (plastic wood), everything true, square, 90 degrees, and redundant.

Personal Opinion: Strive to not suck. But! But!!!!!!

Have fun with the boy. Let him, even as a Tiger, do as much as the decision-making and car design/work as possible. Within common sense rules, of course. Scroll saws and Tigers might not work for you. This year we are doing a cheeze-wedge car. That's not MY decision. It's his. As it should be.

Winning is actually a PITA. (Pain In The, you get it.) Then you HAVE to go to the District Derby and race again. If you follow MY philosophy, and are just there to have fun, then you are going to get your ass spanked at District. Some, are hardcore. I ain't. So, travel over to the District race, run one-and-done. Can be fun, I suppose, but can be a pain.

When the g. is doing more of the car himself, perhaps I will encourage more competitiveness, in a mello way.

Or maybe, I just suck.

Andrew Longman
01-14-07, 11:18 AM
G has some good advice.

To add a little more...

Given the rules of physics any acceleration you gain at the start is multiplied through the run, so you want make sure the car moves with the minimum of effort. That is also helped by having a "high nose" - F1 style, since the start is controlled by a peg that drops into the track. That way the peg doesn't have to travel as far before the car starts to roll.

Weight seems to do better towards the front of the car though I'm not sure why.

Put the wheels and axels in a plastic bag with graphite and keep shaking it to work in and totally coat everything in graphite. The longer the better.

Put a little negative camber in the wheels to reduce friction on the ground but also to put the wheels away from rubbing on the body.

Check for alignment. Make sure it travels as straight as possible.

Once you have everything set, epoxy the axils in place and otherwise make sure everything on the car is secure. The cars actually take a bit of a beating at the finish and you don't want parts (weight) falling off or the wheels going out of alignment.

Good luck and have fun.

RARules
01-14-07, 11:25 AM
600 grit is way too coarse. Some folks sell 2000 or 3000 grit emery paper - presumably for exactly this application. (The same folks sell fancy ~moly-laced graphite - really slick stuff!) I imagine soemthing like "Soft Scrub" might do in a pinch as a fine polishing agent - as it's commonly available, cheap and pretty fine. But messier for the kids. The stock axles are absolutely horrendous. Take off as little material as you can without leaving pits.

A big key is to take all of the flashing off of those really crappy hard-plastic wheels. - including on the axle surface. A fine needle file is handy for that. Also, you might consider tapering the sides of the wheel outsides to minimize the contact patch. Put screw through wheel, mount in a Dreml tool and sand the wheel as you like. Polish it up nicely with your 600 grit (at least) emery paper. Wet sanding works best; otherwise the plastic heats up and burrs up (and throws marbles) if you're impatient/aggressive.

If the child is motivated at all in the project, this can be a good way of discussing the file points of engineering, teaching power tools (a Dreml tool is relatively safe if well-supervised), safety, construction techniques (like glues), etc. The big problem here is that immaculate attention to the fine details are what win these races, and 6 year old kids have very little patience for these details.

It's been a long time since I've done this, but perhaps some races these days might have two (or more) brackets - one for the kids and one for the adults.

Oh BTW, if the child wants a wedge design, go for it. It's easy for all involved and it's an aerodynamic design. Get the weight in the back, of course...

G.
01-14-07, 12:37 PM
All good stuff. You'll find many different opinions on this topic. Go figure.

Careful about treating the wheels. We almost got kicked out of District bc the tech inspector had thick thumbnails. He couldn't feel the little bumps on the outside edge of the wheel and thought that I had sanded the wheel road-surface down so much that they were gone. I had to put the car up to his ear to let him hear that the bumps were there.

This makes no sense, so just be careful about treating the wheels.

Weight in the middle is conventional wisdom, YMMV.

In the front, it helps the start, in the back, good for the finish. So comprimise, put it in the middle.

Winston Wolfe
01-14-07, 01:35 PM
YOU GUYS RULE !!!!! :thumbup:

I knew there were a few dads out there who knew what I mean... I want the boy to have some fun, but I didnt want to overlook the obvious and miss out on some of the experience of the OC board members who may have done this already.

Work commences today on the car.... sandpaper, CHECK. Axels, Check. Wheel adjustments, CHECK.... Dremel is out.

Thanks for all of the tips\advice. :D

devilmaster
01-14-07, 02:55 PM
A thread like this deserves these youtube vids.....

http://youtube.com/watch?v=RuWw2j6Tr0g

http://youtube.com/watch?v=2T9IVZFQ5I8

http://youtube.com/watch?v=wbcEZxq6uqA

I'm just sayin ;)

Spicoli
01-14-07, 04:21 PM
A thread like this deserves these youtube vids.....

http://youtube.com/watch?v=RuWw2j6Tr0g

http://youtube.com/watch?v=2T9IVZFQ5I8

http://youtube.com/watch?v=wbcEZxq6uqA

I'm just sayin ;)

Canaduh. :laugh:

JLMannin
01-15-07, 10:37 AM
There definately needs to be a "Parents Only" competition - some packs have done this - it's like the F1 world of Pinewood Derby. You can buy cheater wheels and axles at a hobby store, but that is not much of a values lesson.

G's advice is really on target. My son was in scouts and did tne pinewood derby twice. Our pack did triple elimination, so each kids car was guaranteed at least three passes. The first year, we were really green and essentially did nothing but add lead to get the car close to 5 oz - three passes, and he was out.

The second year, we worked with the wheels and axles more, and really graphited the wheels and axles. His car made five passes that year, meaning he won two heats - he was happy and he did a lot of the work. He designed it, decided where to add the weight, and did most of the painting. We went to a co-workers house to use his wood shop to cut the wood. He did the wheels and I used emory cloth on the axles.

My son was very satisfied with his accomplishement, and that is the point, in my opinion.

Winston Wolfe
01-20-07, 03:37 PM
Pinewood Derby Update - Pack 639 Den 1

Well, today was the day, and thanks to everyone for their assistance, advice, and recommendations. Due to some late nights for my new job this week, I wasnt fully able to get involved until last night at 7PM. My son was fired up, had designed the car himself, and wanted it to look like "The King" from the movie "Cars". It doesnt hurt that one of my most prized possessions is a 1:24 scale die cast of Richard Petty's 1970 Superbird in my die cast collection.... but I digress.... so the boy is out in the garage with me, working the chisel, the dremel, cutting the metal weights, helping use the magic marker (light blue, kind of close to Petty Blue :D ) and we go to work until about 8:30 when he is worn out...
I finish it up, trying to get the axles smooth, rub in the teflon powder near the wheels, get the weight as close to 5.0000 oz as possible, installed as close to center \ rear as possible, etc.... We used a silver paint marker to get the "43" on the sides, front headlight, and top of the car. Best part of it all, is my son is totally stoked with it, and thinks it'll be the best looking car there...
So we pass tech inspection, and you guys were right ! There were some cars that look as though they had wind tunnel time !!!! All of the other 6 year olds thought my sons car was cool....recognized it as The King from "Cars", even though some of the cars their Dads did had 6 coats of clear lacquer, tapered side pods, hidden weights, recessed and curved bodies and laser straight Shelby Lemans stripes on 'em.... One Dad said he spent 16 hours on the car (and it showed) and a neighbor kids Grandpa has a full on workshop and basically G'pa made the car himself....
Good news is - we got a bunch of 3rd place finishes until the front right wheel got bent a bit and slowed it to some 4ths and even a 5th place. Neighbor kids were scoring 1st and 2nds, but they had 16-20 hrs into their cars and it was clear it had a lot to do with it...
Finally - they announce the awards, and my son got the " I Did It Myself" award, which is cool, because he chose the design, the color scheme, did all the marker work, put the stickers on, did some wood chisel work, held the dremel, polished the axels and was really involved with it ! He was real happy with the results and I'm glad we entered. He got a trophy and an award.... Good times for son and Dad ! that's what its all about :thumbup:

SteveH
01-20-07, 04:27 PM
" I Did It Myself"

In other words he won! :thumbup: He beat all the other kids at this, he just didn't beat the Dads. :D

Congrats to both of you. Great job!

G.
01-20-07, 04:38 PM
THAT'S what I'm talking about!:thumbup:

devilmaster
01-20-07, 05:07 PM
Congrats WW.... :thumbup:

If ya can, get a photo up of the 3 of ya (dad, son, car)....

Do it in the classic Indy 500 qual pose - camera on the front quarter panel, son standing in the cockpit... ;)

Sean O'Gorman
01-20-07, 05:50 PM
Pffffft, if you ain't first, you're last!

Just kidding. This was a good story to hear. When I wanted to start racing, my dad left me to fend for myself, and even though it meant waiting until I was an adult to start autocrossing, it means so much more when you've heard it yourself. :thumbup:

Hard Driver
01-20-07, 06:48 PM
Congratulations. Sounds like you did a good job..

Sorry got into this thread a little late. Do enough Internet searches and you can find anything else you need for next year. My son and I finished cub scouts last year. Our record in pinewood derby was 3 overall first places out of 5 tries, Once to the finals finishing 3rd and one year we were not so great being mid pack in the den.

Tips for next year.
- Make sure the long overhang is in the front.
- Weight should be exactly 5oz, low, with the balance point about an inch and a half in front of the rear axle.
- Buy one of the axle polishing kits and polish your axles to mirrors, including the inside of the nail head.
- Lift up one of the front tires and put offsetting weight on the opposite rear corner so the corner with the tire in the air stays up and if you push it down, it pops right back up. 3 wheels is faster than four, because you only have three wheels of friction. I paired up wheels and axles and then as accurately as possible spin them and see which ones spin the fastest. The axle/wheel that spins the slowest, use that one for the wheel in the air.
- Make sure the car rolls perfectly strait. If the car turns left or right when it rolls, it will rub the center guide more often and slow it down.
- Finish the car a few days early. Get the graphite molybrium dry lube and lube the wheels and axles and roll the car back and forth. You want to pair the wheels to the axles by rolling them back and forth every day for a little bit. A car that has spent some time rolling will be faster than a car that just had the wheels put on.

cart7
01-21-07, 08:23 AM
Here's a place that's got all the tuner goodies:

http://www.abc-pinewood-derby.com/race-management.htm

Joelski
01-21-07, 11:09 AM
Do they still allow lead? Bore the body and fill with heated lead. Sand it all smooth and use all the lead you can, shaving off wood to bring the weight back to 5 Oz. even.

Winston Wolfe
01-21-07, 03:23 PM
I heard about the "hollow out the body and add weight internally" trick. Dont know if they still allow lead.... I do know that mercury and asbestos have been determined to be banned materials, tho' !

I'll try and post of pic of the my boy and his trophy, if I can figger out this innernet thang!

http://new.photos.yahoo.com/herbt66/album/576460762386282691/photo/294928804191889656/1

Maybe this will work ?

If it does, my boy is the one on the right side of the photo, with no cub scout gear on !:thumbup:
The other two boys live on the street and had plenty of wind tunnel time to refine their parents and g'pa designed vehicles ! Naturally, they are holding the 1st and 2nd place hardware...

G.
01-21-07, 05:02 PM
Our Pack mandates that all 4 wheels must touch a flat surface when rolling.

I use lead bullets (not rounds, or cartridges, just the lead!:p ) for weight. Drill a 0.45 in hole and push them in. Conver with plastic wood, or use them for detail. You can slice them with an old knife.

emjaya
01-22-07, 09:46 AM
I heard about the "hollow out the body and add weight internally" trick. Dont know if they still allow lead.... I do know that mercury and asbestos have been determined to be banned materials, tho' !

I'll try and post of pic of the my boy and his trophy, if I can figger out this innernet thang!

http://new.photos.yahoo.com/herbt66/album/576460762386282691/photo/294928804191889656/1

Maybe this will work ?

If it does, my boy is the one on the right side of the photo, with no cub scout gear on !:thumbup:
The other two boys live on the street and had plenty of wind tunnel time to refine their parents and g'pa designed vehicles ! Naturally, they are holding the 1st and 2nd place hardware...

Congats to your son.:thumbup:

ChampcarShark
01-22-07, 12:19 PM
Congratulations :thumbup: :thumbup:

G.
01-27-07, 04:11 PM
One thing I forgot to do this year: True up the axles! I had the car all built and I had a bent axle (sort of) and 3 outer hubs that were not square. I usually borrow a guy's axle press, found here http://www.maximum-velocity (http://www.maximum-velocity.com/specialty_tools.htm#wheelman)
but I thought that I bought one last year. It was too late, I had to make do. I did buff the inside wheel hubs, but I didn't notice that one of the wheels was WAY out of true. The madrel that I usually borrow would have saved some time there. Late night sorting through extra axles and wheels ensued.

You can get (IMO) crazy with polishes, wheel balancers, etc., if that's your thing. One of the Tiger's dad did exactly that. Blew everyone away by over 0.1 sec., which is huge.

End result, 3rd out of 16 Bear Scouts! I didn't expect to do that well, by any means. Not enough time this year, either work, sick g., whatever.

What's the best part about 3rd? First and Second go on to District. Third gets the bling trophy, and doesn't have to go! Woot!

Am I bad?

I had fun. He had fun. A lot. What else matters?:thumbup:

chop456
02-20-07, 09:07 AM
Lowe's is selling Pinewood Derby Kits made by Dremel that include an instructional DVD and (I think) some specialized tools.

Winston Wolfe
02-20-07, 11:01 AM
Lowe's is selling Pinewood Derby Kits made by Dremel that include an instructional DVD and (I think) some specialized tools.

Thanks, Chop... I saw that too.... but our troop had a requirement where you had to use the body supplied by the scout leader. They were all supposed to be the same "type" and supplies, but by the time the Grandpa's and Dad's with full woodworking machine shop setups were done, some of them looked like futuristic vehicles from 2030 !!!
It was a good time to do some bonding with the boy, and he has already started asking me when we are going to Long Beach GP this year. :thumbup:
Its gonna be hard to top some of the stuff he did at last year's race : Got interviewed by KCAL-9 new hottie, got a pic taken with AJ "Almond-dinnner" and got to sit in the N-H race winning Mickey D's car.... we'll see !:D

chop456
02-20-07, 12:18 PM
Its gonna be hard to top some of the stuff he did at last year's race : Got interviewed by KCAL-9 new hottie, got a pic taken with AJ "Almond-dinnner" and got to sit in the N-H race winning Mickey D's car.... we'll see !:D

Just rearrange all those events so that he's taking a pic of dad sitting on the N-H car with a hottie in his lap.

Everybody wins. :D

Sean O'Gorman
02-20-07, 12:42 PM
Lowe's is selling Pinewood Derby Kits made by Dremel that include an instructional DVD and (I think) some specialized tools.

Were any of the specialized tools designed by Chad Knaus?

G.
02-20-07, 01:55 PM
http://www.blackhawkscouting.org/pinewood/cars/lettuce.jpg
We're not that ^^^^^ creative.

rosawendel
02-08-14, 11:19 AM
My son (who is a tiger cub this year) and I participated in our first Pinewood Derby last night.
He won two of his four heats, but did not make the finals. Didn't matter. He was so excited to participate and win a race. it was nice to see.

iPhone photo:
http://i61.tinypic.com/1hxgs9.jpg


The pickup in the background was my attempt at an adult division entry. it was too heavy, and I wasn't able to drill out enough weight to participate.

G.
02-09-14, 03:26 PM
My son (who is a tiger cub this year) and I participated in our first Pinewood Derby last night.
He won two of his four heats, but did not make the finals. Didn't matter. He was so excited to participate and win a race. it was nice to see.



The pickup in the background was my attempt at an adult division entry. it was too heavy, and I wasn't able to drill out enough weight to participate.

Nice! Pinewood derby's are a lot of fun, if the dad doesn't go overboard.

Regarding weight - the pine that they give you is light weight. Any extra wood that you may add is made from the stuff inside black holes, even if it's pine. :)

Forstner bits are your friend.

611




I swear, every time we add a couple of pieces of wood to a car, we need to remove as much as the original wood block, just to make weight. ;)




I'll try to get a pic up later. It might be appreciated here...

G.
02-09-14, 11:31 PM
This car took 2nd in Class, with no controversy from the judges. ;)


613



I basically had to hollow it out from the bottom (2 - 1 inch boreholes). You can actually fit a small adult inside the car. :gomer:

The g. said, "I want to do the Flying Lizard car this year".
(How about a wedge of cheese instead? /inside my head)
"Awesome, which one"?
"The Audi".
(You know they make body kits that look like a 911, right? /internal dialog)
"Sounds Great"!

SteveH
02-10-14, 12:03 AM
Very cool G

Gnam
02-10-14, 02:55 AM
Respect to g & G Racing. :thumbup:

TravelGal
02-10-14, 06:37 PM
Respect to g & G Racing. :thumbup:

:thumbup::thumbup:

rosawendel
01-31-16, 04:25 PM
the 2016 entries:

822
823
824

The boy went for speed. Dad went for "best in show" in the adult category.

SteveH
02-01-16, 10:22 AM
:thumbup:

nrc
02-01-16, 08:10 PM
Very cool. Great work!

G.
02-02-16, 12:10 PM
Those are awesome!

:thumbup:

Elmo T
02-02-16, 12:15 PM
This car took 2nd in Class, with no controversy from the judges. ;)


613



I basically had to hollow it out from the bottom (2 - 1 inch boreholes). You can actually fit a small adult inside the car. :gomer:

The g. said, "I want to do the Flying Lizard car this year".
(How about a wedge of cheese instead? /inside my head)
"Awesome, which one"?
"The Audi".
(You know they make body kits that look like a 911, right? /internal dialog)
"Sounds Great"!

I hope someone sent that photo to the Lizards team!

Napoleon
02-02-16, 02:55 PM
:thumbup:

G.
02-02-16, 07:03 PM
I hope someone sent that photo to the Lizards team!

I sent it to KBrew, but I don't think she got it. (operator error, I'm sure.)


The g. got it signed by Spenser Pumpelly and Nelson Canache Jr. in 2014. They grabbed their cameras and took photos themselves.

TravelGal
02-03-16, 01:54 PM
The g. got it signed by Spenser Pumpelly and Nelson Canache Jr. in 2014. They grabbed their cameras and took photos themselves.

:thumbup::thumbup: