My old shop teacher in Dayton said to score the fold twice and I ignored him for a whole year
Back in 2019 I was pressing signatures with a single score line because it felt faster, and the spines on my notebooks kept cracking after a couple of weeks of use. My old shop teacher, Mr. Halverson, had told me to score both sides of the fold with a bone folder before sewing, but I figured it was fussy extra work. After three cracked spines in a row on a batch of 15 journals, I tried his way and the folds lay flat without a single split. Now I keep a bone folder within arm's reach at all times. Does anyone else score both sides, or have you found a different trick that holds up better on heavier stock?