Legality of lifting front wheel

[JohnNC]

First of all, thanks to all who have posted such insightful tips and techniques for pwd preparation and car construction. Pack 316 held their PWD today and we swept the championship. Never lost a heat, never had a car closer that one body length. Thanks to you guys we pushed the CG to one inch in front of the rear axle, coned the hubs, used Stan's shim method to get dead on, and tried out Ny-Oil. All tips that we would not have tried had we not joined this extremely helpful forum. (BTW, we run a thin wedge, lift a front wheel, and do the standard wheel/axle treatment)

We are excited now about Districts. But I have a question for the collective brain trust. A father at pack told me he thought that it was illegal to lift a front tire based on district rules. We have done this at the pack and district level before, with never a problem. But this year, our wheel is really lifted, perhaps 1/16 of an inch off the ground.

The only rule that I see that might apply is "Axles must be in the same plane and visible for inspection." How would you interpret this rule? Would that outlaw a lifted front wheel?

Thanks for your thoughts.

[terryep]

Sounds like a one of those "fun sucking" rules to me. Try to dumb down the competition or make cheaters out of the winners.

Terry

[Stan Pope]

But this year, our wheel is really lifted, perhaps 1/16 of an inch off the ground.

The only rule that I see that might apply is "Axles must be in the same plane and visible for inspection." How would you interpret this rule? Would that outlaw a lifted front wheel?

The first question I would ask you is whether your axles are "in the same plane?"

Some ways that his might be interpreted include:

1. the center line (axis) of the axles lie in the same plane. This is very exacting. To raise the tread 1/16" off the track, you would have to reduce the radius of the wheel morethan 1/16"! Probably disallowed, but possibly not.

2. there is a plane which contains some part of each axle shaft. This is pretty sloppy, and, since the axles are a bit more than 1/16" in diameter, the lifted axle could easily be parallel to the others and part of the axle be cut by that hypothetical plane. It is even easier if the axles are not required to be parallel, but I like parallel axles, even for the lifted axle.

I think that you need to talk to the district PW chairman and find out how this rule is (or is not) going to be interpreted and enforced.

[Stan Pope]

BTW, while you are asking, find out how the axle that is hidden by the wheel and by the wood of the car can be left exposed?

[DR Pine]

JohnNC

I think Stan said it best confirm it from the horses mouth (PW derby chair).

[JohnNC]

What a quandry. The irony is that last year we didn't intend to lift an axle but due to our mechanical ineptitude we accidently had a front tire slightly lifted. Serendipity I guess.

This year when when my son and I spent time and effort doing research, tested a couple of models and techniques, and tried to work hard within the rules to be successful, you get a curveball with district rules (one or two that are rather ambiguous and difficult to quantify) that are different from our packs. Philosophically, I place far more value on the benefit of the PWD process for my son (research, construction, science/physics, learning, socialization) than results - winning or losing. But it is frustrating to think about getting to registration and having an issue and perhaps having to perform car modifications at the last second.

Stan, I think I will contact the District PWD chair and see what their take is on the rule "Axles must be in the same plane and visible for inspection." I wonder now if canted wheels would be outlawed as well as a lifted wheel since they would not be in the same plane, right? And visiblility is also hampered by the glue/epoxy that we use.
I may also raise the issue if it is the "car or the boy" that is qualified. Cars are not impounded and we have a 4 wheel back-up wedge.

Sorry for the long post, but now that I have vented to those who probably can understand my dilemmna I feel better.

Lesson: Next year we will build by district rules, not pack.

[Cory]

Sounds like a one of those "fun sucking" rules to me. Try to dumb down the competition or make cheaters out of the winners.

Terry

Yep, awful rule. It's hard to see anything at all that's good about this one.

[Alex]

Why should it be illegal to lift a wheel? Everyone knows about it. This year Dad only helps me with power tools that might be dangerous. Last year he taught me about lifting a wheel, how to do it and the advantages. PWD has helped me know a lot more about physics than the other kids in my class inclding my teacher. Our principle had me give a talk about some of the things I have learned about physics to the fith graders in their science class I have learned that can be useful in real life situations. In case some might not know, without using precision instuments one wheel out of four is always carring less weight than the others. With rear weighting the less dominate wheel will be a front wheel. Any rule that doesn't let us intentionanally lift a front wheel is a rule that keeps us from learning about other mechanical. I love being a scout. But sometimes I think they make rules that keep us from learning. Why? I want to have fun, learn fairplay and good sportsmanship, enjoy racing, enjoy competing. and really like to win. But I do not like a sore loser. That would disapoint my dad if I was one. All the things about Pinewood racing are good, why take away the chace to learn new things too. Maybe they have there reasons. I wish I knew what they were. God Bless us all, especially the Scouts. Alex

[Stan Pope]

Alex,

I agree with all your reasons why they have a "dumb rule." There seems to be no disagreement with your argument.

The problem is this: The rule has been made and communicated to all of the participants. Dozens, maybe hundreds, have built their cars in accordance with the rule, and they would be at a disadvantage if some were allowed to violate the rule.

It really is too late this year to change the rule. The cars have already been built!

<pinebox_mode>

I sounds like the rule has not been consistently applied in past years. That is not a good situation, but this year's judges must be bound by the mistakes of last year's judges.

</pinebox_mode>

[Whistler]

FWIW we found that it was almost impossible to enforce the "all axles in one plane/4 wheels in contact with the track" rule in our pack. It was much too difficult for the boys to ensure that 4 axles were coplanar and wheels were of identical diameters with the machining tools available to them, not to mention the difficulty in achieving alignment with two front "steering" wheels (not to bring up that whole discussion again, but we seem to have much less trouble aligning a 3 wheel car than a 4 wheel car). With the new PinePro tools this is less difficult, but not everyone is going to purchase those. I know there are other techniques that have been indicated on this site that outline methods to achieve this using jigs and a drill press, but not everyone has access to one of those either.

With many kids still using the slots, this rule, if enforced rigorously, becomes somewhat exclusionary. In my opinion, a scout should be able to build a PWD car that fits within the rules with a sharp pocketknife and a little ingenuity. The car may not win, but at least he could race. Rules that remove this possibility are counter to the spirit of the event.

We dropped that rule after one year's inspection showed a preponderance of cars were submitted that didn't meet it.

[DR Pine]

We ran the four wheels touching the track rule are 2003 and what we learned confirms what has been previously mentioned. It is an effort for the boys to have all four touching and while enforcing the rule we saw many cars making last minute adjustments that had negative effects on there performance. This year we allowed three wheelers.

In conclusion this rule seems to try and balance competition but our experience is that a knowledgeable car builder can produce an either a competitive three or four wheeler with relative ease. Where as four wheels touching creates more of an obstacle for the inexperienced builder.

[Stan Pope]

this rule seems to try and balance competition but our experience is that a knowledgeable car builder can produce an either a competitive three or four wheeler with relative ease. Where as four wheels touching creates more of an obstacle for the inexperienced builder.

Excellent observation! Those subjected to the 4-wheels touching rule should pass DR Pines posting on to their rule-makers, please!

[dper]

We don't have an "axles in the same plane" rule in our races. I can't imagine the need for such a rule. However, take comfort in the fact that most of the friction on the wheel that you want to "lift" is eliminated as soon as the car is not supported by the wheel. The wheel does not have to be lifted high enough to not rotate when the car moves. In fact, one could argue that a wheel that stays still while the car is moving has an increased drag when it bangs against the track center guide (compared to one that is free-rolling down the track but not supporting the car.)
I try to just have one front axle lifted enough so that I can feel a click when I press the front of the car down near that wheel, but not enough that the wheel doesn't rotate.

[dper]

I suspect that the guy who wrote the "all in one plane" rule wasn't thinking of lifted wheels. I have a hunch he was thinking of someone turning the lifted wheel axle straight up and down so that the wheel rolls on the edge of the center guide and looks like the circular brush on the front corner of a street cleaning machine used for sweeping the gutters.
Just a guess though. I suppose that would make the car too wide anyway.

[Stan Pope]

We don't have an "axles in the same plane" rule in our races. I can't imagine the need for such a rule. However, take comfort in the fact that most of the friction on the wheel that you want to "lift" is eliminated as soon as the car is not supported by the wheel. The wheel does not have to be lifted high enough to not rotate when the car moves. In fact, one could argue that a wheel that stays still while the car is moving has an increased drag when it bangs against the track center guide (compared to one that is free-rolling down the track but not supporting the car.)

The point of lifting a wheel is not to eliminate friction with the axle. The increased weight on the other wheels quickly make up for that.

The purpose is to avoid expending energy to spin up that wheel, using it for linear speed instead.

If all 4 wheels are spinning, then it doesn't matter (much) how many of the wheels are supporting the body's weight. (The "much" qualifier relates to nonlinear compression of the wheel material, which is a virtual non-issue.)

Of course, alignment and track smoothness must be good enough to delay the center rail contacts that cause the wheel to spin up.