I'm not sure if this device is used in quilting or not, but several people had suggested that it might have been used by a quilter or weaver, so I thought that I would ask on this newsgroup to see if anyone had seen one of these before.
Here are two photos of it:
The owner's description of it:
It was in the "stuff" belonging to my Aunt Jane, who recently died.
It appears to be hand-made.
Several of my aunt's brothers (my uncles) ran a machine shop for many years, so this may have been some sort of prototype.
When the object is folded flat, the holes on opposing sides line up; when the object is opened into a square, the holes on opposing sides also line up.
The oddly-shaped piece I will label the "tab" appears to have no function other than holding the piece flat when it is folded, and the fit when it is folded down is not snug.
For reference, I will call the edge of the object on which the tab is attached, the top.
Along the inside of the bottom of the object, there is a recessed section running across all four sides, from the bottom edge to just above the row of holes; this creates a ledge or lip just above the holes.
For scale, the object is 8" long when folded flat. When opened square, the outside edge is roughly 4-1/2", and the inside edge is 4". The lip is recessed ¼".
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Please let me know if you recognize it.
Thanks, Rob