First, apologies in advance if I bring up that already discussed here. A quick search here finds me no such dialogue.
My thread discusses the history and beauty of the expanding round table. I suspect it's something that many woodworkers have at one point seen, in some incarnation.
(Conflict of interest: I bear no fiduciary relationship to anyone mentioned here.)
Invented by Jupe and patented in 1835, https://www.youtube.com/watch?v=sigKxn4R-Ik
, the table, when spun expands its leaves out from the center, exposing gaps in the structure, in which additional leaves, stored separately, can be placed to increase the table's area. Circles, as we know, enjoy the geometric ability to increase area exponentially with size (pi X radius squared) as compared to the rectangles most tables are created in.
Since that time people have expanded (no pun intended) on Jupe's initial work, incorporating design changes, different materials other than wood, and automation e.g. https://www.youtube.com/watch?v=fkQRArX7tec
. In different ways, leaves have been designed to stored with the table, but in a folded state in which "one or two motion" opening of the table was not possible.
There's even this table, https://www.youtube.com/watch?v=gXWmqZPyRw4
, whose brilliant design I consider such a departure from Jupe, that I don't consider to an evolution of this "bloodline."
But the most significant advances to Jupe's work, most believe are those of DB Fletcher.
Fletcher's most notable improvement (and he's made many) I think is the introduction of a "star" into the table's center. This allowed the aforementioned leaves to be smaller, and not have to extend to the table's center, which in turn allowed them to be stored within the table itself, albeit at a lower level when the table is in its smaller state, in a non-folded state. Fletcher has also added significant improvement to materials and mechanism, using wood more as a surface laminate that construction material--opting instead for use of an aluminum honeycomb structure in the leaves that is strong, lightweight, and most important, more dimensionally stable than wood: an important feature when trying to get pieces to line up as close to perfectly as possible. His hardware is brilliant, and specific to the table. All these changes allow the table to be changed in size with one or two motions.
This is my favorite video of the table:
because it allows people to see, in slow motion, the genius and "ballet" behind its design as those 12 arced pieces in the middle, that branch out, allow the table to expand, to allow the leaves space to rise from lower levels, and then allow those "always on the top" leaves to slightly contract back to close the table back.
DB Fletcher also deserves cudos for creating the table skirt that makes the table appear round in both its smaller and larger sizes.
In his design, the table is only truly round (as arcs can only be truly round it one specific diameter) in the large state. Technically, in the small state the leaves form a faceted structure. But the skirt's inside routing "absorbs" these smaller state geometric (not sloppy construction based) imperfections to roundness, presenting on its outside, a round structure--hence the table appears round in small and large states.
Sadly though, most of us cannot recreate DB Fletcher's designs, despite his patent expiring, nor afford his price to purchase the table. His manual tables (as opposed to automatic ones) start at tens of thousands of dollars (US).
In my opinion, a recent, positive, and significant paradigm change to this table has emerged. Scott Rumschlag, of Mechanical Lumber, has created a version of the table, and documented it as such for others to reproduce http://mechanicallumber.com/
in affordable and clear cut plans that include videos on Youtube and Google Sketch images that supplement conventional plans. Scott works primarily with wood on this table, and includes features in his design that recognize and address wood's inherent imperfections as it relates to strength and dimensional stability over time.
Scott's table is not round in its large state--although I suspect this of little concern to the do it yourselfer. He's always improving upon his plans, offering such design improvements for free to existing plan licensees. His most recent of improvements has been the creation of a (round) table skirt, using techniques that don't involve steam bending or kerfing wood. Scott has an uncanny ability to incorporate off the shelf hardware, often with little or no modification required for its use in the table, to allow people like us to create (and afford to create) this design for ourselves. By no means is the project quick or easy, anymore than it is impossible thanks to Scott's work.
I would enjoy hearing what others have to say about this table.