<br><br>While the flour-based stuff is easy and fun, it's not permanent. Even with metallic dopants, it will shrink and crack when dry. I'd be more interested in exploring plasticine or some of the new polymer modeling clay formulations. I'm assuming the bulk resistance of these are pretty high -- which is good for insulating matrix.<br>
<br>I really think there might be something to making capacitors by stack-squish-repeat operations (like phyllo dough) on alternate conductive and dielectric layers, <br><br>C = conductive, "-"=insulating, start with two layers (side view)<br>
<font class="Apple-style-span" face="'courier new', monospace"><br></font><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">CCCCCCCC<br>CCCCCCCC<br>--------<br>--------<br></span><br>
cut in 1/2 and stack<br><br><div><font class="Apple-style-span" face="'courier new', monospace"><span class="Apple-style-span" style="font-family: arial; "><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">CCCC<br>
CCCC<br>----</span><div><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">----<br></span></div><div><span class="Apple-style-span" style="font-family: 'courier new', monospace; "><span class="Apple-style-span" style="font-family: arial; "><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">CCCC<br>
CCCC<br>----</span><div><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">----<br></span></div></span></span></div></span></font><div><br></div><div>flatten to original height with rolling pin:<br>
<br><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">CCCCCCCC<br>--------</span></div><div><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">CCCCCCCC</span></div>
<div><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">--------<br></span><br></div><div>and repeat arbitrarily.<br><br>Not sure how this works exactly, but if we can connect alternate conductive layers c and C by leaving alternating dielectric edges on the non-cut dimension, and adding conductive walls, voila we have a capacitor between C and c:<br>
<br><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">CCCCCCCCCC-c<br>C----------c<br></span><span class="Apple-style-span" style="font-family: 'courier new', monospace; ">C-cccccccccc<br>
C----------c<br></span><br>This can be repeated until the layers are fractally thin. Every repeat doubles the capacitance, so in the limit you could make nanoscale structured capacitors with huge areas (square km?) and theoretically huge capacitance. Wonder what the practical limit is? <br>
<br><br>On Thu, Jul 29, 2010 at 6:27 PM, Josh Myer <<a href="mailto:josh@joshisanerd.com">josh@joshisanerd.com</a>> wrote:<br>> I think the metal dopants are great for us, and we should totally run<br>> with them, carcinogens or not. We just need to remember not to let<br>
> Ada (et al) eat this otherwise-edible play-doh.<br>><br>> Is it plausible that we're going to create actual conductive matrices<br>> of these dopants, or are they just there to lower the net resistance?<br>
> --<br>> /jbm<br>><br>> (I will neither confirm nor deny the rumor that Al eats play-doh.)<br>><br>> On Thu, Jul 29, 2010 at 5:52 PM, Jonathan Foote <<a href="mailto:jtfoote@ieee.org">jtfoote@ieee.org</a>> wrote:<br>
>> Super interesting!<br>>><br>>> I had to look up "candurin" listed in the ingredients of the silver icing<br>>><br>>> Basically, it's Ti02-coated mica nanoparticles: the same stuff they<br>
>> put in shampoo to make it pearlescent (and in the awesome<br>>> Exploratorium shimmer globe).<br>>><br>>> <a href="https://webcache.googleusercontent.com/search?q=cache:WA_mqbLu4GQJ:www.merck-chemicals.com/pharmaceutical-ingredients/candurin-silver-colors/c_wN2b.s1L2KwAAAEWGywfVhTn+">https://webcache.googleusercontent.com/search?q=cache:WA_mqbLu4GQJ:www.merck-chemicals.com/pharmaceutical-ingredients/candurin-silver-colors/c_wN2b.s1L2KwAAAEWGywfVhTn+</a><br>
>><br>>> Note zero silver, just two of the best insulators on the planet! So<br>>> the conductivity in the icing must come ionically from whatever else<br>>> is polar. Christoph, did you measure the resistance when it was dry?<br>
>><br>>> (Also note that TiO2 was recently classified as a possible carcinogen:<br>>> eat up those yummy nanoparticles!)<br>>><br>>> So I'd still like to find a conductive dopant that works when dry.<br>
>> I've seen powdered aluminum (for use in thermite, among other fun<br>>> things) but I don't know how conductive it is (aluminum in the<br>>> atmosphere undergoes almost immediate oxidation to get a coating of<br>
>> insulating Al0) -- does anybody know?<br>>><br>>> -J<br>>><br>>><br>>><br>>><br>>><br>>><br>>><br>>> On Thu, Jul 29, 2010 at 3:26 PM, Christoph Maier<br>
>> <<a href="mailto:cm.hardware.software.elsewhere@gmail.com">cm.hardware.software.elsewhere@gmail.com</a>> wrote:<br>>>> On Thu, 2010-07-29 at 14:31 -0700, Michael Shiloh wrote:<br>>>>> This should be well photographed. There will be much interest in the<br>
>>>> results.<br>>>>><br>>>>> I'm willing to contribute a scope probe that can get doughy. For<br>>>>> science, of course.<br>>>><br>>>> Too bad I'm busy with squishy circuits here in San Diego ...<br>
>>><br>>>> Christoph<br>>>> <a href="http://pony.noisebridge.net/~cmaier/recherche_du_temps_perdu/">http://pony.noisebridge.net/~cmaier/recherche_du_temps_perdu/</a><br>>>><br>>>><br>
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>>> <a href="https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss">https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss</a><br>>>><br>>> _______________________________________________<br>
>> Noisebridge-discuss mailing list<br>>> <a href="mailto:Noisebridge-discuss@lists.noisebridge.net">Noisebridge-discuss@lists.noisebridge.net</a><br>>> <a href="https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss">https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss</a><br>
>><br>><br>><br>><br>> --<br>> Josh Myer 650.248.3796<br>> <a href="mailto:josh@joshisanerd.com">josh@joshisanerd.com</a><br>> _______________________________________________<br>> Noisebridge-discuss mailing list<br>
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