New Great Lakes Field Service Council rules for 2019

[DocJancsi]

After four years of racing in the GLFC council races, and experiencing the all too familiar questions regarding interpreting and enforcing the rules, I decided to accept an invitation to provide feedback to the Council after last year's race. As no good deed goes unpunished, I was asked to write a completely new set of rules. As someone who can cite peer reviewed journal articles on "Gravity Powered Racing" this is a bit like asking the fox to guard the hen house.

My approach was to treat the derby as an opportunity to teach and demonstrate STEM principles specifically the engineering process while providing a reasonably level playing field so that every scout could build a winning car with the help of an adult and resources which would commonly be available at the den level.

I wanted to provide clear and testable limits while intentionally allowing some wiggle room within those limits for experimentation. Wherever possible I wrote the rules to be objective and relevant to the science of the derby and the prevailing practice within the Pinewood Derby Racing Community.

I was given the following limitations by the other members of the Pinewood Derby Committee:

1. No Oil or thin film lubricants allowed (I argued in favor of it but was shot down).
2. Tools and materials available in the Scout Shop for purchase will be legal (except oil!)
3. Using a lathe for the purpose of reducing the rotational inertia of the wheels will be illegal.


I also want to thank the North Star Council. I shamelessly stole the format and some of the wording from your excellent 2017 rule set. It is your own fault for publishing the best set of rules for the Derby available online.

I have attached the rules for the 2019 GLFC Pinewood Derby below. I am asking the community for feedback and constructive criticism. How could these rules be improved?

 

[bracketracer]

"3.9. Wheels must be free to contact the body of the car. 3.9.1. Washers placed on the axle or attached to the body are prohibited. 3.9.2. Any otherwise legal material permanently attached to the side of the car shall be considered a part of the car body.
Body treatments to help reduce friction ARE ALLOWED. Body treatments (between wood chassis and wheel) may be things like sprayed on graphite paint, Teflon tape, other slippery materials/waxes applied to the body."

So Teflon washers are illegal but I could attach a sheet of Teflon film to the side of the car?

 

[bracketracer]

"4.3. Wheel dimensions must NOT deviate from the following dimensions: 4.3.1. Maximum Exterior Diameter: 1.170 Inches 4.3.2. Maximum Width: 0.360 inches 4.3.3. Minimum Tread Thickness: Unmodified wheel – 0.010 inches 4.3.4. Minimum Sidewall Thickness: Unmodified wheel – 0.005 Inches 4.3.5. Minimum Weight: 2.5g"

Maximum diameter is 1.17"? Maybe you meant minimum there?
You probably need to specify a minimum tread width or guys will run cut down razors.
Tread thickness of .010" on an unmodified wheel? Do you mean you can only remove .010 or leave .010"?

 

[bracketracer]

"5.9. No foreign material or object may be permanently attached to an axle."

So domestic material that is removeable is fine?

 

[bracketracer]

"7.1. Lead (Pb) weight, if used, must be completely sealed and safe from all possible contact with youth. 7.1.1. The parent or guardian of the Scout must ensure safe materials are used. Toxic or Radioactive materials (e.g., Lead in any form, Thoriated Tungsten welding rods) should be avoided."

Lead is ok, unless it's lead. Then it needs to be avoided?

 

[DocJancsi]

"3.9. Wheels must be free to contact the body of the car. 3.9.1. Washers placed on the axle or attached to the body are prohibited. 3.9.2. Any otherwise legal material permanently attached to the side of the car shall be considered a part of the car body.
Body treatments to help reduce friction ARE ALLOWED. Body treatments (between wood chassis and wheel) may be things like sprayed on graphite paint, Teflon tape, other slippery materials/waxes applied to the body."

So Teflon washers are illegal but I could attach a sheet of Teflon film to the side of the car?

Under these rules, any body treatment except for a washer would be legal.

In my first draft I specifically included both free and fixed washers as a permitted modification. I received additional guidance from the old guard.

"4.3. Wheel dimensions must NOT deviate from the following dimensions: 4.3.1. Maximum Exterior Diameter: 1.170 Inches 4.3.2. Maximum Width: 0.360 inches 4.3.3. Minimum Tread Thickness: Unmodified wheel – 0.010 inches 4.3.4. Minimum Sidewall Thickness: Unmodified wheel – 0.005 Inches 4.3.5. Minimum Weight: 2.5g"

Maximum diameter is 1.17"? Maybe you meant minimum there?
You probably need to specify a minimum tread width or guys will run cut down razors.
Tread thickness of .010" on an unmodified wheel? Do you mean you can only remove .010 or leave .010"?

There are two errors here in both cases the rules should read minimum exterior diameter and minimum thickness.

Where the dimensions are given as Unmodified Wheel - x. That is how much material may be removed from the dimension. Measure an Unmodified wheel or several and take an average. Measure the wheel on the car with a no less than -.010 tolerance.

As far as I know, the exct dimensions of a standard derby wheel beyond diameter and width are unpublished. This requires measuring unmodified wheels. There will be some slop as the tolerences on stock wheels are fairly loose.

"5.9. No foreign material or object may be permanently attached to an axle."

So domestic material that is removeable is fine?

This is intended to prevent the use of graphite coated axles. A removable material would count as a bushing. Foreign here means foreign to the axle. If it is not from the original axle it’s not allowed.

In theory Lemon Pledge, Sail-Kote, or Jig a Loo could be included here. It was not intended to include them nor is their presence easily detectable.

I am not dragging a Gas Chromatograph/Mass Spectrometer to our council race. It would take too long to rough down.

"7.1. Lead (Pb) weight, if used, must be completely sealed and safe from all possible contact with youth. 7.1.1. The parent or guardian of the Scout must ensure safe materials are used. Toxic or Radioactive materials (e.g., Lead in any form, Thoriated Tungsten welding rods) should be avoided."

Lead is ok, unless it's lead. Then it needs to be avoided?

We would ban lead weight entirely if we could. We know because of its availability it will be used. Stating in the rules to avoid using it and requiring that lead be sealed away with paint will minimize exposure of the kids to lead before and after the race.

I have seen kids playing with cars after the derby with cars covered in lead (not graphite). We know a lot more about the dangers of heavy metal exposure in kids than when the derby first started. As a medical professional I could not in good conscience ignore the issue.

 

[Briggs_Power]

Under these rules, any body treatment except for a washer would be legal.

In my first draft I specifically included both free and fixed washers as a permitted modification. I received additional guidance from the old guard.




There are two errors here in both cases the rules should read minimum exterior diameter and minimum thickness.

Where the dimensions are given as Unmodified Wheel - x. That is how much material may be removed from the dimension. Measure an Unmodified wheel or several and take an average. Measure the wheel on the car with a no less than -.010 tolerance.

As far as I know, the exct dimensions of a standard derby wheel beyond diameter and width are unpublished. This requires measuring unmodified wheels. There will be some slop as the tolerences on stock wheels are fairly loose.


This is intended to prevent the use of graphite coated axles. A removable material would count as a bushing. Foreign here means foreign to the axle. If it is not from the original axle it’s not allowed.

In theory Lemon Pledge, Sail-Kote, or Jig a Loo could be included here. It was not intended to include them nor is their presence easily detectable.

I am not dragging a Gas Chromatograph/Mass Spectrometer to our council race. It would take too long to rough down.



We would ban lead weight entirely if we could. We know because of its availability it will be used. Stating in the rules to avoid using it and requiring that lead be sealed away with paint will minimize exposure of the kids to lead before and after the race.

I have seen kids playing with cars after the derby with cars covered in lead (not graphite). We know a lot more about the dangers of heavy metal exposure in kids than when the derby first started. As a medical professional I could not in good conscience ignore the issue.

I do like how you added thoriated tungsten welding electrodes. Im a tig/stick pipe welder so I'm aware of the dangers involved with thoriated tungsten, but they work really good for what I do so I still use them. But I wouldn't want my kids using them..

 

[Dscross]

We just had our pack race under these rules. Um... there were questions. Like when we measured 5 blocks directly from the BSA boxes and they didn't measure to 1.75 inches.
One question we had was about graphite pads. Are they legal or not?
As the way the rules were written I build a few Family and freinds cars from Balsa wood. I glued pine craft sticks to the side, and drilled the axel holes through the pine, thus connecting the axel to the body... it touched pine. It was mostly an experiment, and the bare body didn't weight much. I didn't have time to do much work on axels or wheels, besides alingment, so the car didn't get very good times, but it looked pretty cool. (The pink wheels car is kevlar over balsa for my daughter, the gold dome with the ornate patern is mine, both are Kevlar layered over balsa with pine where the axels meet the body. The red roadster is mine as well. ) Those are the cars I build while watching my son work on his.

 

[DocJancsi]

We just had our pack race under these rules. Um... there were questions. Like when we measured 5 blocks directly from the BSA boxes and they didn't measure to 1.75 inches.
One question we had was about graphite pads. Are they legal or not?
As the way the rules were written I build a few Family and freinds cars from Balsa wood. I glued pine craft sticks to the side, and drilled the axel holes through the pine, thus connecting the axel to the body... it touched pine. It was mostly an experiment, and the bare body didn't weight much. I didn't have time to do much work on axels or wheels, besides alingment, so the car didn't get very good times, but it looked pretty cool. (The pink wheels car is kevlar over balsa for my daughter, the gold dome with the ornate patern is mine, both are Kevlar layered over balsa with pine where the axels meet the body. The red roadster is mine as well. ) Those are the cars I build while watching my son work on his. View attachment 1251

There are 2 specification in these rules regarding width of the car neither of which should cause problems by the width of the block not measuring exactly 1.75”

The first is the maximum width. That is not to exceed 2.75” this is not a new measurement and this standard was taken from previous rule sets. All of the “test boxes” were cut to this dimension.

The second spec which could be affected would be the stance. This is the distance between the inner edge of the treads this must be a minimum of 1.75”. This is intended to clear the width of the guide rail for most tracks. Best Track for example has a 1 5/8” guide rail.

It was the intention of the committee that the axles be inserted into pine wood. The design you describe would not meet this requirement. Your axles are inserted through pine wood and inserted into balsa. In other words, the majority of the length of your axles are touching balsa and not pine. Therefore that design and construction does not meet that requirement. A ladder style body cut from pine with a rung for the front and rear axles reinforced with balsa ribs is ok as would 2 pine ribs
connected by balsa.

As to the graphite pads, under these rules anything permanently attached to the body to reduce friction is ok. A free floating washer or bushing riding on the axle is not. Does this answer your questions?

 

[Dscross]

There are 2 specification in these rules regarding width of the car neither of which should cause problems by the width of the block not measuring exactly 1.75”

The first is the maximum width. That is not to exceed 2.75” this is not a new measurement and this standard was taken from previous rule sets. All of the “test boxes” were cut to this dimension.

The second spec which could be affected would be the stance. This is the distance between the inner edge of the treads this must be a minimum of 1.75”. This is intended to clear the width of the guide rail for most tracks. Best Track for example has a 1 5/8” guide rail.

It was the intention of the committee that the axles be inserted into pine wood. The design you describe would not meet this requirement. Your axles are inserted through pine wood and inserted into balsa. In other words, the majority of the length of your axles are touching balsa and not pine. Therefore that design and construction does not meet that requirement. A ladder style body cut from pine with a rung for the front and rear axles reinforced with balsa ribs is ok as would 2 pine ribs
connected by balsa.

As to the graphite pads, under these rules anything permanently attached to the body to reduce friction is ok. A free floating washer or bushing riding on the axle is not. Does this answer your questions?

Yes, thank you. My son's car was build with the BSA pine kit just incase. However I should tell you that all the judges at the race read your rules, looked at my Balsa and craft sticks and agreed that it adhered to the rules. So FYI, you might want to keep that in mind when you write next years rules. Now suppse I'm off to build a balsa with pine axel ribs car while I watch my son slowly... finish his car. Oh he works so slowly... lol. Thanks for your answer.

 

[Bw56]

pm sent.

 

[Dscross]

I of course forgot to ask the other question we had. Axels. A few things. Would something like the Javilen Stainless steel axels be ok? Again we errored on the safe side and polished our own. However We have one of the axel straigtening tools, and when using it, it flatened the axel heads. I read this as illegal, so put them aside. Would the use of this tool, be legal? Sorry to bombard you, just feeling lucky that I have the guy here who wrote the rules we're operating under.

 

[Dscross]

pm sent.

I either didn't get it, or can't find it because I'm new...

 

[Pinewood Outlaw]

"5.9. No foreign material or object may be permanently attached to an axle."

So domestic material that is removeable is fine?

Lol....dang I had some Turkish Damascus tungsten I wanted to use.

 

[flockshot]

As a rookie, is it safe to assume that if something, for instance modifying or cupping the hub, is not mentioned, then it is fair game, or do things like that need to be specifically 'allowed'?

 

[Mojo Racing]

Unless it says "Don't", you can do it.

But there is that stupid rule "all 4 wheels must touch". It doesn't say don't, but says must. Those are the kind you have to do.


I wish we could get some of the pack and district rule makers who actually put "4 wheels touching" into their rules to step up and give us an idea as to why they put that in there. I am almost positive some of the cub masters who are out there are doing this and read this forum... step up... let us know why, please.

 

[Bw56]

Anyone who has helped young scouts put their axles in (Even as adults) knows getting 4 touching is not as easy as it sounds.

 

[Mojo Racing]

That was how I was able to get away from that when I was helping the district.

We went to a pack with 30 cars and had cubs put their axles in. More than 20 were not riding on 4 wheels

 

[Bw56]

" More than 20 were not riding on 4 wheels"Mojo Racing. And how many also were accidental railriders? LOL Might as well go for that rule also.

 

[Mojo Racing]

what rule, no rail riding?

No kidding... have a boy make a car that runs straight on 4 wheels ! ! ! Good luck with that?

This is essentially drag racing... and with any form of racing... the idea is to go faster...