Magnet question

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miko
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Magnet question

Post by miko »

11. The car must be freewheeling with no starting devices.

Does anyone think this makes magnets illegal? There is no mention of magnets in our rules otherwise.

Thank you
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FatSebastian
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Re: Magnet question

Post by FatSebastian »

miko wrote:11. The car must be freewheeling with no starting devices. Does anyone think this makes magnets illegal?
It depends on whether the magnet intends to act as a starting device. If the magnet imparts momentum to the car from the starting pin when it is dropped, or if it is part of some other propulsion system, then "Yes".

(I cannot think of a good reason to want to include a magnet except to assist propulsion somehow.)
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Darin McGrew
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Re: Magnet question

Post by Darin McGrew »

FatSebastian wrote:(I cannot think of a good reason to want to include a magnet except to assist propulsion somehow.)
I've used magnets to keep parts of the car together during the race, that needed to be easily removable for design reasons. Normally I use epoxy or other glues to attach parts permanently, and small screws to attach parts that may need to be removed later (e.g., a decorative car body attached to a thin chassis made from the original kit). But some designs have needed to come apart more easily, while still remaining securely attached during the race.

FWIW, our starting pins are aluminum, so magnets wouldn't be very effective as a starting mechanism.
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Re: Magnet question

Post by rpcarpe »

If I were in the judge's shoes and found a magnet... I'd probably ask you to remove it.
And as Darin pointed out, aluminum (or any non-iron) start pins negate the usefulness of a magnet in the nose.

If there are metal parts in the track, the magnet will draw the car towards them as it approaches and as it attempts to leave them. Not sure if there is anything to gain there.

Our own rules state: "4. Gravity powered only. No power assist devices such as rubber bands or magnets."
Makes sure no one tries anything crazy. That's what Outlaw races are for.
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sporty
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Re: Magnet question

Post by sporty »

miko wrote:11. The car must be freewheeling with no starting devices.

Does anyone think this makes magnets illegal? There is no mention of magnets in our rules otherwise.

Thank you
Whats your thinking here ?


Most start gate pins are wooden or aluminuim. not metal

The only thing that comes to mind, IS atempting to add copper wire into the rear wheels and a magnet on the body, a powered magnet to get the wheels to spin faster.

Not sure it would even work, but the only real guess I can take, at what you might be wanting to do.

Sporty
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gpraceman
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Re: Magnet question

Post by gpraceman »

sporty wrote:Most start gate pins are wooden or aluminuim. not metal
Or stainless steel. The Micro Wizard and Best Tracks use stainless steel screws for the start pin, which are non-magnetic.
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Stan Pope
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Re: Magnet question

Post by Stan Pope »

gpraceman wrote:
sporty wrote:Most start gate pins are wooden or aluminuim. not metal
Or stainless steel. The Micro Wizard and Best Tracks use stainless steel screws for the start pin, which are non-magnetic.
I believe that the section join screws on the Freedom track are also stainless steel. Section join screws are a bit trickier to leverage from, and even more so than had they been steel, but still a source of mini-kicks along the way.

I wonder at the status of stainless steel ... the attraction of a magnet to stainless steel is definitely way less than to mild steel, but it seems to me that there is still some weak attraction between my stainless steel rod and my little magnet. In the world of PWD, a "little kick" is often all that is needed.

Rolling a magnet above a mild steel screw would have the effect of speeding up the car as it approached the screw and slowing down the car as it left the screw. The net effect would be to increase the average speed. However, since the screw is below the plane of the magnet's motion, the attraction would also temporarily increase the force in the bore friction equation and offset some or all of the benefit. A few easy experiments should tell if the net effect is beneficial or not. Now, if the permanent magnet in the car were replaced with an electromagnet which is energized only when the magnet is approaching the screw ... Perhaps if the track were longer it could function like a mass driver and allow the car to reach escape velocity! Ummmm... probably need a bigger battery for that! :)
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