This looks like a normal 4-hole Japanese Stab Binding, but it has a secret.
Instead of the normal page with a fold at the fore-edge, this little book has double-folded pages which create a flat double-page spread at every second opening. The folding to achieve this is quite simple.
To make my model, I started with strips of paper about 46 cm/18″ long and 10 cm/4″ wide, and folded them in half. I then folded up 1.25 cm/0.5″ at the bottom edge of the top layer on each piece, flipped the paper over and folded up the same amount at the bottom edge of the new top layer.
The next step involved folding the top edge down almost to the upper edge of the bottom fold. I left a 0.6 cm/0.25″ gap as indicated by the pink pointy finger.
Keeping the top layers in position I unfolded the bottom layer and its little flap so that the folded edge was at the top.
I then reversed the fold indicated by the pink pointy finger above.
The top edge of the folded paper above becomes the fore-edge of the book and the bottom edge becomes the spine.
From this point on the procedure was the usual one for making a 4-hole Japanese Stab binding. If you have never sewn this type of binding before, there are excellent instructions by Grace Bonney here.
I find it helpful to use two pieces of book board and a pair of spring clamps to hold everything in position while piercing the holes and doing the sewing.
Once sewn, the book has two alternating types of page opening. The opening between the page units looks like a traditional Japanese stab binding.
The middle of each page unit provides a flat-opening double page spread.
The 0.6 cm/0.25″ space I left between the spine fold and the centre fold of the double page spread was more than I really needed for the very flexible Thai Unryu paper. A little experimenting will be needed to establish how much space to leave for whatever paper you are using.
If you wish to do a fancier sewing on your model, Becca Makes Faces has a wonderful collection of decorative stab binding patterns, many with step-by-step instructions.
You can find her site here.
Hilke Kurzke also recently posted a method for flat-opening pages in a stab binding.
Hilke has reduced the pattern of the stitching to a decorative element on the spine of a pamphlet binding. You can read all about it here.
In other book arts news:
Robert Bolick has two recent posts on items from the Books on Books Collection which will be of interest to many: Claire Van Vliet and Elizabeth Steiner’s 2002 publication Woven and Interlocking Book Structures and Roberta Lavadour’s Origins (2018). Both posts contain multiple images of the works as well as a list of supplementary links to related items in the internet.