Copying wouldn't be legal--the web site says its patented, although it doesn't say where. The following US patents might be relevant: 6009814, 6994032. --ms greenwald@cis.upenn.edu wrote:
Mon, 11 Dec 2006 07:56:12 -0800 Henry Baker <hbaker1@pipeline.com>
I suppose that it could be strictly circular if the band around the smaller table isn't of fixed thickness, so that it can hide the larger radius pieces within itself.
If the smaller circular band is of constant thickness, then there will be gaps in the table top where the radii don't match.
I single-stepped the movies to try to see the smaller circular band better, but the movie appears to jump discontinuously at just the right moment -- perhaps to hide the shape of the smaller circular band from potential copiers.
I assumed it was not constant width/thickness --- that's what I meant by an inscribed, rounded, "hexagon".
I, too, couldn't see the detail in the movie. I doubt, though, that the discontinuity was intended to hide anything. First, this seems like one logical way to construct such a table, but once you see the table itself, surely you can think up a couple of different ways of implementing it. Second, a potential copier could simply look at a real example of such a table.
(The tricky part, I'd guess, would be the alignment of the vertices of the inner "hexagon" and the outer ring --- wouldn't they have to be pretty accurate in order to avoid gaps in the smaller table? Although, I suppose you could build it with a bit of give --- so that they get nudged into place as the table compacts. I'm sure furniture builders have many ways of getting around this problem, though, so my guesses as to what's hard and what's easy are probably worthless.)
In any case, I found the table and mechanism extremely pretty.
At 07:43 AM 12/11/2006, greenwald@cis.upenn.edu wrote:
Mon, 11 Dec 2006 07:32:25 -0800 Henry Baker <hbaker1@pipeline.com>
Very cool, but not strictly circular.
Why not? Doesn't the ring that encircles the table when it is in compressed mode make it strictly circular? (The outside of the ring appears to be a circle with the 6-person radius. The inside of the ring could be an inscribed "hexagon" with arcs (with the 12-person radius) instead of lines. When the table is expanded, the outer edges of the inner pie-wedges/segments join to form a circle.)
At 07:58 PM 12/10/2006, Ed Pegg Jr wrote:
A nifty circular table based on dissections is available. With a spin, it becomes a table twice as large as before. The mechanism is beautiful.
Fletcher Capstan Tables http://www.dbfletcher.com/capstan/
--Ed Pegg Jr
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