I finally stopped cutting my spine liners too narrow, and my books open so much better
For my first 20 or so case bindings I kept cutting the mull and paper spine liners flush with the text block spine, and every book ended up with that stiff hinge that cracks when you open it flat. My mentor at the Raleigh book arts guild showed me that the liner should extend onto the boards about 1/2 inch past the joint on each side, and now my books open smooth with no creaking sound. Went back and fixed three old projects and the difference was night and day. Has anyone else here had trouble getting the liner width right, or is it just something you figure out with reps?