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Diamagnetic materials make stable magnetic levitation possible as they have a non-polar magnetic field that repels foreign magnetic fields. This may one day serve to advance humanity; however, a better air hockey table should be our first priority!
Using pucks made of granite, graphite or bismuth
(pink hockey pucks?) and an electro-magnetic substrate for the table surface, the thin, wafer like puck should hover about 2mm above the playing surface.
Without the air holes blowing your perfect shot off course, the action should be faster, and deadly accurate. Increase your alcohol consumption, and the game becomes just deadly.
Warning: Owner should not wear ferrous metal jewelry while playing. It is quite sporting to encourage your opponent wear large ferrous ornaments around his neck. Pacemakers should be turned off while playing.
Further Warning: This game is not for children with tiny little fingers that can be easily severed.
Diamagnetic Levitation
http://www.physics.ucla.edu/marty/diamag/
[1st2know, Oct 17 2004]
(?) The baking
diamagnetic_20hockey
[spidermother, Feb 24 2006]
Superconductor and magnet
http://www.metacafe...o_can_explain_this/
Came across this, and thought it might be interesting for some. [Ling, Sep 15 2006]
[link]
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If you could do this with Pool... |
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Unless you have tried this i dont think you could make any puck stop flipping itself over as i have learned from years of childhood play with magnets.
the thickness of the puck is a bit of a problem how do you play with a wafer thin puck. and large diamagnetic tables would cost a pretty penny to feed in electro juice. |
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Seem to remember from physics that unless you have a perfect diamagnet (which is another way of saying a superconductor) then you will lose energy in the form of eddy currents and the puck will settle onto the table. I don't know if room temperature superconductors exist yet, but if they do they're gonna be pretty expensive. So you're looking at having either a puck or a playing surface that's cooled by liquid nitrogen to skin-blistering temperatures. But thats not necessarily a bad thing. Combined with the high speed of the puck, you could market this as Table Hockey For Real Men. |
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Okay, I'm no scientist, but what about the fact that a granite puck is going to hurt like hell if it hits your hand? or not happily bounce like the crappy plastic ones? |
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[abraxas] The idea of diamagnetic levitation is to use materials that *repel* a magnetic field - these materials, like bismuth, have no polarity - so if it flips over, and during the course of the game it may, then it should just continue levetating on its other side. |
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[spacemogg] I dont think super cooling is needed with diamagnetic materials, however, I subscribe to the belief that liquid nitrogen doubles the fun of any game - look for it in version 1.1 :-) |
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[imagine002] good point. Warnig message modified. |
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Eddy currents will be a problem - could be solved
somewhat by changing the structure of the puck (eg.
strips of magnetic material with an insulator between);
but the high speeds and acceleration of the puck might
thwart it anyway. It's a catch-22: the properties needed
for good levitation are also the perfect properties for good
magnetic damping. Creative engineering could probably
find a comprimise, though - never say never, when air
hockey is concerned. + |
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And you need liquid helium for superconductors, I think. |
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Depends on the superconducing material. I believe Yttrium Oxide can be cooled at temperatures involving liquid nitrogen. |
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The loud part of the hockey table is the fan that blows the air. Just attach a vaccuum hose from the table to a built-in vaccuum machine, and run the sucker backwards (bypassing the dirty filter, of course). |
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I have a small version. It’s about 4" X 8". |
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This is what it cost me to build |
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It cost about 100.00 dollars in materials not including labor. |
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If I were to build a larger table when I did the math it came out to about 4,000.00 dollars if I could get a number of people to buy it for 8000.00 dollars it could be profitable. It is quite labor intensive to build. |
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I do not use a superconductor. |
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There is no need for any refrigeration unless your house gets above 165 C. |
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Eddy currents do not appear to be an issue the faster you hit the puck the faster it goes at least on the small version. |
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The puck is thin lightweight and super strong however it is not indestructible. I will provide 3 pucks with the small version. |
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The puck floats between .5mm to 1mm above the surface of the table. |
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It can support a piece of paper glued to the top of it that is the same size so it can come in any color you want. I have not tried to paint the puck yet. |
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The magnetic fields are contained within a mumetal shield on the bottom and the sides. However, metal will stick to the top of the table. I would recommend not wearing a watch while playing. |
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Holy biscuit dough! Nobody ever *makes* things on the HB! That would require initiative, goal setting and other achievement behavior stuff. We only hope that Bristolz illustrates our ideas. |
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So, where is it and when can I come over to play? |
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On the price, you think you could let me have one for about $142? What is the puck made from? (Bismuth is my secret favorite!) NO LIQUID NITROGEN! For eight grand, I’m going to be expecting some freeze juice. |
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Please post a photo – I will be up all night, mashing reload on this site waiting for photos. For authenticity purposes (and as a silly cliché) please show a current daily paper with the days headlines (ie, “Cheney Goes on D.C. Shooting Rampage”). |
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[1st2know] Photos here (link). |
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Just the other day I was at a party where someone had made a tiny diamagnetic levitating table: a square inch or so covered with rare-earth magnets, floating a piece of pyrolytic graphite above them. Looked neat. |
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I imagine [ed68wood]'s was a similar but larger version. |
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