James "Xakh" Lynch
superstuff7 at gmail.com
Fri Jul 23 20:02:53 EDT 2010
why don't we just put a kickstand on the top of the screen, like with that
aluminum strip on the top, maybe making it flip outward? It seems sort of
pointless to make a counterweight, and waste valuable internal space.
On Fri, Jul 23, 2010 at 12:57 PM, Werner Almesberger <werner at openmoko.org>wrote:
> James Xakh Lynch wrote:
> > You sure we couldn't use a different metal? One that isn't so toxic? I'm
> > sure if I'm okay with having the nanonote associated with large
> > of lead...
> With my current estimates for shape and placement I need something
> with a density of about 10 g/cm3 or more. This list is handy for
> possible choices:
> Bismuth would be a good choice. The ~17 g we need would cost only
> about USD 0.3. A "Ben Silver Edition" or, better, a "Gold Edition"
> would work, too. Molybdenum and particularly tungsten would be
> more economical choices, but they're both difficult to shape.
> Copper and nicket may already be too light.
> Since tungsten has a density of 19.25 g/cm3, the center of the
> counterweight could be closer to the front, reducing the mass
> needed to perhaps as little as 10 g. At today's market price of
> USD 30/kg, that would cost only 0.3 USD, as much as bismuth.
> So if future NanoNotes need a counterweight, bismuth and tungsten
> may be an affordable choices for large quantities.
> That is, if all this works as calculated. We'll see.
> - Werner
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