When finishing the hand binding of a single signature book, a decision must be made where to tie off the knot: inside or outside of the cover. On the outside, the knot and the extending thread will be immediately visible. If tied off at the center of the book, the knot and extending thread are seen only when the book is open to the center fold? It’s a knotty question (pun intended), but basically which way to finish of the sewn thread is rooted in your aesthetic sense.
When tied off on the outside, the book (booklet, pamphlet) has a home-made feel to it, marking it immediately as something not normally found other than in publications that have a limited distribution. An outside knot can become an attractive feature enticing a buyer to acquire your book. On the other hand, an inside knot has its own charm. The book with such construction has a smooth spine which will focus a reader’s attention immediately to the cover vs. to the sewn knot. When finished this way, a reader is treated at the centerfold to a visible hand-finished knot, a reminder that the book is out of the ordinary.
Either way, you can’t go wrong. Sewing so the thread is outside or inside makes no difference in cost, so let your sense of what you want your book to represent and how you want it to be presented guide you in your choice of inside or outside.
Until later . . .