04-19-2009, 10:05 AM
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#11 (permalink)
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EcoModding Apprentice
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What's the cost of a magnet ???
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04-19-2009, 10:21 AM
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#12 (permalink)
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Pickup Fuel Meiser
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Blackline - '09 Nissan Frontier King Cab SE V6 Jetta - '11 Volkswagen Jetta Sportswagen TDI
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I'm no engineer, but it seems to me that a magnetic engine might not be best suited to a mobile platform like a mower or car due to its complication and need for precision. Instead, I would think the best application for this would be power generation, whether it be a small, home-powering unit or scaled up into a massive power-plant sized unit. Then we all just build/buy electric cars and we're all set.
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04-19-2009, 11:27 AM
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#13 (permalink)
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needs more cowbell
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I would say the default assumption here is that magnet motors are not sustainable as the magnets give up their magnetism for a minuscule amount of rotational energy. They have been around for decades ("Power Wheel" Popular Science, Fall 1980), and trade magnetism for rotational energy. No free lunch. If Bill were not soliciting I wouldn't care.
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WINDMILLS DO NOT WORK THAT WAY!!!
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04-19-2009, 06:35 PM
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#14 (permalink)
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EcoModding Lurker
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Plate tectonics??
Quote:
Originally Posted by cfg83
Could you make the argument that a massive amount of energy went into making the rare-earth magnet (plate tectonics), and that you are just making use of it?
CarloSW2
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Carlos, I have no idea how plate tectonics might be involved. The "rare earth" magnets (neodymium, samarium, etc.) I'm referring to are charged up in a high electromagnetic field during manufacture. The magnetic field of the planet is relatively low, and variations are measured in nanoTeslas per the reference at
Earth's Magnetic Field Calculators - Instructions
If you meant something else, please explain bearing in mind that I am not in any sense a person with a strong background in magnetic science nor quantum theory. I'm an experimenter, and base those experiments on gross behaviours of magnetism and lots of cut-and-try.
Thanks,
Bill Whedon
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04-19-2009, 07:14 PM
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#15 (permalink)
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Pokémoderator
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Bill -
My mistake. I confused "rare earth" (the material used in manufacture) with natural origins.
CarloSW2
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04-20-2009, 11:48 AM
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#16 (permalink)
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Cost of a magnet
Quote:
Originally Posted by HaroldinCR
What's the cost of a magnet ???
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The magnets I'm using cost anywhere from $1 to $several, depending on strength. The 80LB ones I use are a couple dollars each. I buy from K&J Magnetics online. They provide better prices than most, and very good fast service.
All the best, God Bless,
Bill Whedon
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04-20-2009, 12:11 PM
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#17 (permalink)
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Leaky magnets?
Quote:
Originally Posted by dcb
I would say the default assumption here is that magnet motors are not sustainable as the magnets give up their magnetism for a minuscule amount of rotational energy. They have been around for decades ("Power Wheel" Popular Science, Fall 1980), and trade magnetism for rotational energy. No free lunch. If Bill were not soliciting I wouldn't care.
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I test my magnets frequently against a magnetometer. To date, in or out of a motor, I've never seen any of the rare-earths lose any of their "pull force".
In another post, you mentioned "keeper" which with a simple flat disc magnet isn't appropriate. A "keeper" according to what I can recall, is a metal bar kept across the poles of antique "horseshoe magnets" most of which were made of magnetized steel, which would lose power over time, to prevent that from happening. The keeper touched both poles. A fridge magnet tends to be hanging on by one pole only, so I don't get how that would apply.
There's a bunch of literature on the rare-earth magnets online at kjmagnetics.com which is where I buy my supplies, and I don't recall anything suggesting that they will drain from use, nor any suggestion that one needs to use a keeper to keep same from happening. I know the things can lose power due to excessive heating, but that's not the same thing.
A lot of information about magnets of one kind doesn't strictly apply to others. For example, the demagnetization of neodymium magnets occurs at arount 175F while samarium magnets hang on through around 570F.
I have to conclude that there is a lot about the things we simply don't know.
Magnetometers are relatively inexpensive, and even more so are the kind I use, made of a transparent plastic tube about a foot long in which resides a pair of opposed short disc magnets mounted in a thinner tube that slides inside the bigger one. That is calibrated by hand using a "Sharpie" marker, and gives only an indication of approximate pull force.
One of the reasons I think that magnetism is a quantum phenomenon is the very fact that it doesn't seem to "drain" in use (with rare earth units). There may be some decay that I've not tested for, but I haven't seen it happen.
You do make me think!!
Cheers, God Bless us and grant us the wisdom to make magnets work for us!
Bill Whedon
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04-20-2009, 02:08 PM
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#18 (permalink)
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Master Novice
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I'd sure love for this to work. I've seen the videos of some of the prototypes spinning up, but there's always something a little odd about the presentation that makes me doubt: the model sits on a large solid base, there's no sound, something.
I guess for me to completely believe in it, I'd have to be able to hold a running one in my hand for over an hour, nothing under or around it. My cellphone has to be able to keep working while the motor's running. It needs to not suck my neighbor's pacemaker out through his nose, and it needs to not take a devout faith in Orthodox Paganism to make it work.
I really want it to work. I just don't think it will. I think that once you've got one going, it's going to come out that ultimately it's using up energy.
I'm no physicist, not an engineer, and have forgotten more about magnetism and the related formulae than I care to think about. But I'm pretty sure that no matter how you slice it, a functioning no-ongoing-power-input magnetic engine demands overunity, and you just can't have that. There's something in the energy equations that's being missed.
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04-20-2009, 03:04 PM
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#19 (permalink)
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EcoModding Apprentice
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Might not be related to this thread, however, I sold Wind generators for several years, back in the 70's-80's. One brand used bar magnets to create the electricity, by spinning the magnets, mounted on the inside of a steel cylinder, around the wire wound coils that were stationary on the fixed hub of the alternator.
I doubt that the magnets ever got too weak to produce electricity. ???
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04-21-2009, 03:27 AM
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#20 (permalink)
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aero guerrilla
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Quote:
Originally Posted by HaroldinCR
Might not be related to this thread, however, I sold Wind generators for several years, back in the 70's-80's. One brand used bar magnets to create the electricity, by spinning the magnets, mounted on the inside of a steel cylinder, around the wire wound coils that were stationary on the fixed hub of the alternator.
I doubt that the magnets ever got too weak to produce electricity. ???
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In a wind generator (or alternator) magnets are used to transform rotational energy into electrical energy, while in a magnetic motor the magnets themselves are producing the rotation. The magnets are a source of energy, and that energy must come from somewhere.
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