MagLev C

[chalker]

Also, does anyone know why the commercial tracks have one north and one south strip in the first place?

i'm wondering the same thing. would the two magnetic fields possibly interfere with each other otherwise? I can't see any other advantage.

I believe it's just a matter of construction ease/cost. Many of the original commercial tracks were made by laying small bar magnets side by side down the length of the track. As a result, you have to have N on one side and S on the other. A lot of the tracks now use magnetic strips, but since most strips are sold in matching pairs, it's easiest to just buy a set and again put N on one side and S on the other.

[Balsa Man]

....and should I even broach the subject of friction-reducing wheels mounted on the sides of the car (rotating about a vertical axis so that they touch the sides of the track) or would that label me as a trouble-maker??

Trouble maker? Not in my book.... Being smart and using science, to solve problems, within the rules of the game; uh, I think this is what the building events are all about.
That is a good solution for minimizing friction.

[Balsa Man]

Also, does anyone know why the commercial tracks have one north and one south strip in the first place?

i'm wondering the same thing. would the two magnetic fields possibly interfere with each other otherwise? I can't see any other advantage.

I believe it's just a matter of construction ease/cost. Many of the original commercial tracks were made by laying small bar magnets side by side down the length of the track. As a result, you have to have N on one side and S on the other. A lot of the tracks now use magnetic strips, but since most strips are sold in matching pairs, it's easiest to just buy a set and again put N on one side and S on the other.

OK, I'm missing and/or misunderstanding something. We're using "small bar magnets side by side" - a bag from Pitsco 1" x 3/4". Kids went through and marked the polarity on all of them- a "+" on one side (as in one of the 1"x3/4" flats). Whether that's N or S, don't know, and it doesn't matter. When you position two magnets with the + sides coming together, they repell. On both track strips, these magnets are glued end to end, with the + side up; same polarity. Magnets on the chassis plate are positioned w/ the + side down. The vehicle is levitated, and able to run levitated, in both directions.

What I don't follow is your statement, "you have to have N on one side and S on the other." I'm sorry, but ....no, you don't. There is absolutely nothing preventing doing both track strips with the same polarity- N up on both, or S up on both. What you do on one side has no effect on the other side- in no way constrains the choice of orientation. Also don't see how which way you choose to flip/place them has any construction ease/cost ramification.
What is it I'm missing?

[joeyjoejoe]

What you do on one side has no effect on the other side- in no way constrains the choice of orientation. Also don't see how which way you choose to flip/place them has any construction ease/cost ramification.
What is it I'm missing?

Actually, there is still the question of whether or not placing magnets the same way on both sides of the track eases the restriction of the removable magnets mentioned in the rules (3k). Configuring your track/car in this way means it can travel in both dir with no mod but some have mentioned that they experienced deductions due to a "violation" of rule 3k.
There is also this other thing that our teams independently verified: cars traveling on N-N tracks/cars (or S-S obviously) experienced less track contact due to rotation of the car than N-S tracks/cars did.
Has anybody else experienced this or was it just a coincidence?

[iwonder]

I think that's true too, I had a track a few years ago that had opposite poles, and the vehicle tended to twist in the track, now I have a track with the same poles on both sides and it goes from side to side, not rotating.

[Schrodingerscat]

I think that's true too, I had a track a few years ago that had opposite poles, and the vehicle tended to twist in the track, now I have a track with the same poles on both sides and it goes from side to side, not rotating.

It can still twist with the same polarity on both rails.

[iwonder]

I'm not saying it can't twist, I've twisted it before by hand and it's stayed that way, but it doesn't show as much tendency to twist... Then again, this vehicle is way better in design than my previous vehicle...

[Balsa Man]

What you do on one side has no effect on the other side- in no way constrains the choice of orientation. Also don't see how which way you choose to flip/place them has any construction ease/cost ramification.
What is it I'm missing?

Actually, there is still the question of whether or not placing magnets the same way on both sides of the track eases the restriction of the removable magnets mentioned in the rules (3k). Configuring your track/car in this way means it can travel in both dir with no mod but some have mentioned that they experienced deductions due to a "violation" of rule 3k.
There is also this other thing that our teams independently verified: cars traveling on N-N tracks/cars (or S-S obviously) experienced less track contact due to rotation of the car than N-S tracks/cars did.
Has anybody else experienced this or was it just a coincidence?

I sent in a clarification question to that specific point - we'll see what comes back.... It doesn't say "moveable", or "removable", just "able to modify placement, so that the vehicle can travel both ways."
As to the report of one ES coming up with a "deduction", that sort of (no doubt well-intended) 'freelancing'-making up new/additional rules is, IMHO, just wrong; they're supposed to apply the rules, equally to all competitors.

Interesting observation of the difference in side contact on NN/SS vs NS tracks; hard to say anything about what may be going on, unless the cars, and tracks were identical- very minor differences could be the cause...

[Flavorflav]

....and should I even broach the subject of friction-reducing wheels mounted on the sides of the car (rotating about a vertical axis so that they touch the sides of the track) or would that label me as a trouble-maker??

FYI, in previous years wheels have been interpreted as illegal based on nearly the same "fully levitated" and "inadvertent contact" language present in this year's rules. I don't agree with the reading, but I would advise you to ask for a ruling from your site.

[Balsa Man]

....and should I even broach the subject of friction-reducing wheels mounted on the sides of the car (rotating about a vertical axis so that they touch the sides of the track) or would that label me as a trouble-maker??

FYI, in previous years wheels have been interpreted as illegal based on nearly the same "fully levitated" and "inadvertent contact" language present in this year's rules. I don't agree with the reading, but I would advise you to ask for a ruling from your site.

Thanks for that insight. Given that, getting a ruling does seem in order. Given that a) the "inadvertent" contact language ...simply ignores (or reflects a complete lack of understanding of) physical reality- contact is inevitable & unavoidable, and b) that whatever the form of contact points - edge of vehicle, little contact "feelers", wheels, has nothing to do with "levitation", such an interpretation is....IMHO, ....unfortunate and......silly. But what is, is. Sounds like we have a similar take. Hopefully, a rational clarification will be forthcoming. Word limitation on the Rules Clarification form makes....making the case a bit challenging.