Pinewood Derby

Discuss anything with like-minded people.
No posting of copyrighted material.

Moderators: mpallett, bakerjw, renegade, Hush

User avatar
silencertalk
Site Admin
Posts: 33985
Joined: Mon Apr 25, 2005 9:31 am
Location: USA

Pinewood Derby

Post by silencertalk » Tue Dec 21, 2010 11:46 pm

My son has to enter. From talking to other fathers, they seem to consider it cheating to build the best car legal within the rules. In fact it seems common that whenever a kid or father builds an advanced car which wins, some local Boy Scout groups create local rules to ban those advancements "to make it fair for everyone."

That seems to be BS. To them being fair means making all cars equally bad so that it becomes random chance who wins. Why not reward the kid who learns about what makes the car faster and then does all he can?

Another problem with local rules that are more restrictive than BSA rules is that if you win the local race, you have no chance at the state or national level.

Even my son seems to be brainwashed. I said "We can polish the axles to reduce friction." He said "That is cheating." I tried to explain to him that getting an advantage from trying harder than other people is not cheating.

I want to nickel plate the axles and lathe-turn the wheels to true them. The rules only say 'dry lubrication only.'

User avatar
Greg Kulbick
Silent But Deadly
Posts: 446
Joined: Tue Feb 17, 2009 10:39 pm
Location: Tallahassee, FL
Contact:

Re: Pinewood Derby

Post by Greg Kulbick » Tue Dec 21, 2010 11:49 pm

Its only cheating if you get caught.
www.renegade-armament.com
01 FFL/03 SOT

User avatar
Hush
Silent But Deadly
Posts: 65404
Joined: Wed May 18, 2005 8:07 pm

Re: Pinewood Derby

Post by Hush » Wed Dec 22, 2010 12:23 am

You can't have a winner or first, second and third place winners because then the other children who lose will feel bad and they can't have that, after all it is "for the children".
Demand stringent background and mental health checks on your politicians.

User avatar
doubloon
Silent But Deadly
Posts: 11901
Joined: Thu Jan 01, 2009 1:02 am
Location: Houston-ish

Re: Pinewood Derby

Post by doubloon » Wed Dec 22, 2010 1:27 am

Polishing the axles is the biggest "edge" and just about the only legal "modification". Everybody and his brother has secret polishing formulas and techniques.

You probably still need to polish the axles before you plate them.

Most people use graphite for the dry lubricant, some resort to a graphite molybdenum disulfide mix ... you should go all out and use tungsten disulfide :D
http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

User avatar
Twinsen
Silent But Deadly
Posts: 7693
Joined: Tue Sep 04, 2007 11:34 pm
Location: AZ

Re: Pinewood Derby

Post by Twinsen » Wed Dec 22, 2010 1:34 am

It's cheating to have the axles trued up as well. 90 degree angles are for cheaters.

User avatar
doubloon
Silent But Deadly
Posts: 11901
Joined: Thu Jan 01, 2009 1:02 am
Location: Houston-ish

Re: Pinewood Derby

Post by doubloon » Wed Dec 22, 2010 1:36 am

hmmm ... after a quick search it looks like lathed wheels must be OK since you can buy BSA lathed wheels for $20

http://www.amazon.com/gp/product/B001F9 ... 4YMS23GBXH

polished axles ... "speed" axles ...

Makes me miss the days when the starting gates were steel and a small magnet buried in the nose gave you a little edge :wink:

Image
http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

User avatar
jdj
Elite Member
Posts: 653
Joined: Thu Dec 13, 2007 12:24 am
Location: Hanover, NH

Re: Pinewood Derby

Post by jdj » Wed Dec 22, 2010 2:03 am

I used to try to mix performance and speed - one year we made a convertible, the next year a drag car - always polished the axles and wheels and used graphite lubricant.

A friend made hubcaps out of paper which held a large amount of graphite and really helped kill the friction.

The point of (any) competition is not equality, it is to innovate, change, and develop new techniques to dominate the competition.
"I regard virginity as a correctible perversity of no interest" - Lazarus Long (Time Enough for Love), Robert A. Heinlein

User avatar
bakerjw
Elite Member
Posts: 3615
Joined: Fri Jul 06, 2007 9:13 am
Location: NE Tenn.

Re: Pinewood Derby

Post by bakerjw » Wed Dec 22, 2010 7:35 am

doubloon wrote:Makes me miss the days when the starting gates were steel and a small magnet buried in the nose gave you a little edge :wink:
My brother in law was a judge at a pinewood derby where a father had done this. He adamantly denied knowledge that it was magnet. All other cars had lead weight in the rear where it was easy to drill out to meet weight requirements. So this father who had no clue about magnetism and proper placement of weight got his son disqualified. It was pretty sad.
July 5th, 2016. The day that we moved from a soft tyranny to a hard tyranny.

flip
Elite Member
Posts: 1469
Joined: Fri Jul 25, 2008 3:01 pm
Location: indiana

Re: Pinewood Derby

Post by flip » Wed Dec 22, 2010 8:07 am

The cars we made in shop class in 7th grade were powered by CO2 cartridges. Winning usually meant by the time the car hit the stop at the other end it was in 2 pieces.

User avatar
pneumagger
Silent But Deadly
Posts: 3455
Joined: Mon Jul 23, 2007 9:09 am
Location: N.E. Ohio

Re: Pinewood Derby

Post by pneumagger » Wed Dec 22, 2010 1:12 pm

WS2 (tungsten disulfide) coat the axles. WS2 is an extremely slick plating or coating... I'm pretty sure it would qualify as dry lubricant. Also, some nylon 6 or ptfe thin-film washers between the wheel hubs and the nail heads or body would decrease edge-rubbing friction. Also, they make ultra-low friction paint that is PTFE impregnated. I would suggest this paint on the wheel hubs and car body and underside of the head of the nail (axel).

Also, I was thinking (when you are truing up the wheels) you could turn a slight convex contour in the wheels to reduce the contact area and rolling resistances against the track. As long as the track isn't significantly soft (unlikely) this should help. Also be sure to polish/lubricate the insides and outsides of the wheels so they don't rub too much on the track guides.

Edit: I just thought of two more things... which may or may not be legal depending on your interperetation of the rules...

If you are truing the wheels using a lathe then hog out the unnecessary wheel material. Less mass means less rotational inertia to overcome at the start.

Secondly, and this should require VERY well polished & lubricated nails, take an appropriate sized tap and run it through the wheel journal. You want the thread's minor diameter to be smaller than the original wheel size so the hole in the wheel has the same effective diameter as before. The tap will have to be positioned with a lathe or mill so it is dead-nuts straight. Then lightly hone out the thread peaks. You're killing three birds with this stone... reduced wheel journal surface area means less friction, the grooves will hold ALOT of spare graphite/WS2/MoS2 ensuring it never runs dry on you, and through the use of right-hand & Left-hand threads you can manipulate the tendancy of the spinning wheel to ride AWAY from the body.

I would say it counts as a form of recontouring, if not polishing.
Last edited by pneumagger on Wed Dec 22, 2010 1:38 pm, edited 2 times in total.
I reject your truths and substitute my own realities

User avatar
copenhagen
Silent But Deadly
Posts: 1109
Joined: Mon Oct 18, 2010 8:37 pm
Location: South Carolina

Re: Pinewood Derby

Post by copenhagen » Wed Dec 22, 2010 1:25 pm

Hey Rob, I say go for it. Screw them if they don't want to put forth the extra effort. What is the point if you are not allowed to put legitimate effort into the design? I wonder if that Robar NP3 coating on your axels would help? Just an idea. It is slicker than deer guts on a door knob in my POF when ran dry.

User avatar
doubloon
Silent But Deadly
Posts: 11901
Joined: Thu Jan 01, 2009 1:02 am
Location: Houston-ish

Re: Pinewood Derby

Post by doubloon » Wed Dec 22, 2010 2:20 pm

"electroless nickel" ... interesting ... where is a more detailed explanation?

I see on the web site that the roguard stuff is baked on but how is the np3 stuff applied?
http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

win912
Silent But Deadly
Posts: 317
Joined: Fri Aug 08, 2008 6:38 pm
Location: Massachusetts

Re: Pinewood Derby

Post by win912 » Wed Dec 22, 2010 4:46 pm

I agree that innovation should prevail, but everything has become so lame these days. While teaching my students I explain that as much as "competition" has been portrayed as a bad thing...they will ultimately have to interview for college or a job and either they will be chosen or the next person will. Then I say...."Is that a competition?" They respond yesssssss. So it is what it is. 8) For the record I am the former 1978 Class B Pinewood Derby Champion from my area. 8) Funny thing is I haven't benefitted from that win..not like you'll see me on Yo MTV Cribs anytime soon.

http://www.youtube.com/watch?v=CsNgRmsx-14

win912
Silent But Deadly
Posts: 317
Joined: Fri Aug 08, 2008 6:38 pm
Location: Massachusetts

Re: Pinewood Derby

Post by win912 » Wed Dec 22, 2010 4:53 pm


User avatar
doubloon
Silent But Deadly
Posts: 11901
Joined: Thu Jan 01, 2009 1:02 am
Location: Houston-ish

Re: Pinewood Derby

Post by doubloon » Wed Dec 22, 2010 5:30 pm

http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

kaiserb
New Member
Posts: 2
Joined: Tue Jun 30, 2009 3:07 pm

Re: Pinewood Derby

Post by kaiserb » Wed Dec 22, 2010 5:43 pm

silencertalk wrote:My son has to enter. From talking to other fathers, they seem to consider it cheating to build the best car legal within the rules. In fact it seems common that whenever a kid or father builds an advanced car which wins, some local Boy Scout groups create local rules to ban those advancements "to make it fair for everyone."

That seems to be BS. To them being fair means making all cars equally bad so that it becomes random chance who wins. Why not reward the kid who learns about what makes the car faster and then does all he can?

Another problem with local rules that are more restrictive than BSA rules is that if you win the local race, you have no chance at the state or national level.

Even my son seems to be brainwashed. I said "We can polish the axles to reduce friction." He said "That is cheating." I tried to explain to him that getting an advantage from trying harder than other people is not cheating.

I want to nickel plate the axles and lathe-turn the wheels to true them. The rules only say 'dry lubrication only.'
As a two time participant, I can tell you there is a plethora of advance car parts for PWD card. Wheels and axles are just a start (see below). Most clubs have local rules that create classes for the types of cars. The one we participated in had a "Solo build class" and an "Adult assisted build class" The sad part is many of the kids in the solo class were from single parent homes where there is NO dad to help out.

While local rules can sometimes even the playing field, the creation of draconian rule sets to label tuning as "cheating" are asinine.

http://www.maximum-velocity.com/wheels_axles.htm
New BSA Wheel Style
4090
Official BSA
Pinewood Derby
Matched Speed Wheels
&
4094
BSA Speed Axles


BSA pinewood derby wheels are well designed, but unfortunately the wheels vary considerably from mold to mold. Most of the wheels are not perfectly round and the tread surface is not even.

Our Speed Wheels are official BSA wheels which are sorted by mold number, and then precision machined with a CNC (computerized) lathe for maximum performance. To provide you with an awesome set of wheels, we perform the following operations:

* The wheels are sorted by mold number, and any defective wheels are discarded.
* The wheel tread is lightly lathed to achieve a perfectly round wheel, and a flat tread surface.

If you would like to order wheels with a particular mold number, Click Here.

Benefits

* Round and smooth wheels roll faster than standard wheels.
* Matched mold numbers ensures that the bore diameter and other wheel measurements are identical, maximizing performance.
* The slight weight reduction (due to the lathing process) provides a faster start.


The Official BSA Speed Wheels can be used without any additional preparation. However, the following steps can be performed for additional speed:

* Polish inside edge - Place a wheel mandrel in a drill, mount a wheel on a wheel mandrel, start the drill, and lightly polish the inside edge of the wheel (opposite the spokes) with a polishing compound or very fine wet sandpaper (minimum 600 grit).
* Cone the Inside Hub - Form a cone on the inside wheel hub with the Pro-Hub tool. Click here for more information.
* Polish the Bore - Polish the wheel bore with graphite or bore polish. Click here for more information.

Important Note

The lathing operation removes a small amount of tread surface. The serrated edge is intact. The tread reduction is barely visible to the eye, but is measurable with a caliper. If your race restricts the use of lathed wheels, consider using our specialty tools and supplies to prepare a set of raw wheels.

Technical Information for 4090/4091 Wheels

Wheel Diameter: 1.170 ± 0.001 (Raw Wheels: 1.182 to 1.185)
Wheel Bore ID: 0.096 minimum
Wheel Weight: 2.6 grams/wheel (Raw Wheels: 2.6 grams/wheel)
Brian E

User avatar
silencertalk
Site Admin
Posts: 33985
Joined: Mon Apr 25, 2005 9:31 am
Location: USA

Re: Pinewood Derby

Post by silencertalk » Wed Dec 22, 2010 6:12 pm

Thankfully we have no local rules.

Yes, it would suck to have no dad to help. My Father has none of those skilz. My brother helped me. I won, but I am pretty sure my car was over-weight. I remember they wanted to disqualify my car but my Mother had a can of Tomato paste with a 5 oz net weight and used it as a tare weight. There are two problems with that. One is that net weight is not gross weight. Two is that 5oz of tomato is not a precise unit of measurement. I moved on to the state race and I can't remember if I lost right away or was disqualified or I was late for the race. I think probably I was just late and missed my race slot.

That reminds me.. I was actually the 5th or 6th grade baseketball free-throw champion of my school. I got easily beaten in the state though.

I have a lathe, and we can turn the wheels and axles. Or we can buy BSA legal but modified ones that are already nickel plated. Part of being smart and resourceful is knowing how to manage our time and focus resources. It is better to contract the modification than do it when it comes to parts.

My son should pick them out, as he does in Gran Turismo 5 when he upgrades his STi.

I don't consider buying a complete car to be ethical as it defeats the purpose of doing something with your son. I do consider carefully choosing modified wheels and axles ethical. I don't consider buying a completed body ethical.

It would be cool if I had a CNC mill and my son and I could 3D machine a nice body.

User avatar
TOOL1075
Silent But Deadly
Posts: 1682
Joined: Sun Jan 04, 2009 8:47 pm
Location: Texas
Contact:

Re: Pinewood Derby

Post by TOOL1075 » Wed Dec 22, 2010 7:22 pm

:) my dad certainly didn't have those types of skills or anything, but we had a blast building them together. I still think you should give him as many pointers as you can and explain why they work; if he doesn't want to use them, fine- but at least he will learn.

pinewood derby was fun. I never won.... most of the guys who always won had dads that had some nice tools and enough know-how to use them. we didn't, but I think we had just as much fun.
https://pewscience.com
PEW Science
Professionally Engineered Weaponeering

User avatar
smcharchan
Silent But Deadly
Posts: 2268
Joined: Thu Dec 20, 2007 8:06 am
Location: VA

Re: Pinewood Derby

Post by smcharchan » Wed Dec 22, 2010 8:42 pm

silencertalk wrote:/snip/ To them being fair means making all cars equally bad so that it becomes random chance who wins. Why not reward the kid who learns about what makes the car faster and then does all he can? /snip/
"From each according to his ability, to each according to his need."

Everyone is special. There are no losers. Don't express your true potential, for you may offend your neighbor.

We wanted it. We voted those into office that would implement it. Now we've got to deal with it being taught to our children.

User avatar
Hush
Silent But Deadly
Posts: 65404
Joined: Wed May 18, 2005 8:07 pm

Re: Pinewood Derby

Post by Hush » Wed Dec 22, 2010 10:08 pm

smcharchan wrote:
silencertalk wrote:/snip/ To them being fair means making all cars equally bad so that it becomes random chance who wins. Why not reward the kid who learns about what makes the car faster and then does all he can? /snip/
"From each according to his ability, to each according to his need."

Everyone is special. There are no losers. Don't express your true potential, for you may offend your neighbor.

We wanted it. We voted those into office that would implement it. Now we've got to deal with it being taught to our children.
The Winner :!:
Demand stringent background and mental health checks on your politicians.

User avatar
jimmythebugman
Silent Operator
Posts: 58
Joined: Thu Jun 21, 2007 1:36 pm
Location: Arnold, MD

Re: Pinewood Derby

Post by jimmythebugman » Wed Dec 22, 2010 10:14 pm

all you need to do is to tap the wheels. Adding threads to the inside of the wheels lessens the surface area that comes in contact with the axel. I learned this after i needed it :twisted: My friend and my brother both did this and both got first place at the regional race.

User avatar
silencertalk
Site Admin
Posts: 33985
Joined: Mon Apr 25, 2005 9:31 am
Location: USA

Re: Pinewood Derby

Post by silencertalk » Wed Dec 22, 2010 11:00 pm

Threaded hubs seem to sometimes help.

Ignore the web-lube tests as wet lube is not allowed.

http://www.stanpope.net/pwfrictn.htm

http://www.stanpope.net/pwafm.htm

User avatar
bnutriaz
Silencertalk Goon Squad
Posts: 152
Joined: Wed Sep 19, 2007 1:40 am
Location: South Korea
Contact:

Re: Pinewood Derby

Post by bnutriaz » Thu Dec 23, 2010 5:46 pm

when I was a kid my grand dad helped me build a car that took 1st place one year. I took second place the next year, apparently my dads pinewood derby skills arent as honed as grand dads.

We never cheated, but we debured the axels and polished them up a bit.

Years later in the US Army Infantry I learned a new lesson. "If you aint cheatin' you aint trying!"
HK MP5
AAC M4-2000
AAC Aviator x2
AAC Pilot x2
AAC Stryker2
AAC Evo .45
AAC Cyclone

User avatar
J Krammes
Silent But Deadly
Posts: 551
Joined: Sat Feb 28, 2009 10:35 pm
Location: Pa
Contact:

Re: Pinewood Derby

Post by J Krammes » Thu Dec 23, 2010 5:57 pm

The only rule I remember we had was the weight maximum. I had alot of fun building mine. I actually still have both of my cars and the first place trophy I won for my second car.

Your son's thought on cheating scares me though. I hope you can make him understand what it means to "tweek".

Jeremy
Some of my work. www.jkknives.com

User avatar
Mongo
Silent But Deadly
Posts: 4167
Joined: Fri May 20, 2005 1:27 pm
Location: Texas
Contact:

Re: Pinewood Derby

Post by Mongo » Thu Dec 23, 2010 6:19 pm

I helped my nephew design his car using Solidworks. It really helped him see what it would look like before it was finished.

Image

Made a few changes as it was sawed out and carved. But you can see I printed a set of plans for it.

Image
Firearms Engineer for hire on piece work basis.
No job is too expensive :)
http://weaponblueprints.com/

Post Reply