Paper weight (measured in GSM - Grams per Square Meter) plays a major role in how a folded design behaves. If the pages are too thin, the folds won't hold shape; if they are too thick, the book will spring open too wide.
The Paper Weight Scale
- Thin Paper (50 - 70 GSM): Found in mass-market paperbacks or dictionaries. Very easy to fold, but delicate and prone to creasing or tearing. Not recommended for beginners.
- Medium Paper (80 - 100 GSM): Found in standard hardcover novels and textbooks. The absolute sweet spot! It has enough stiffness to hold a crease but folds smoothly.
- Thick Cardstock (120+ GSM): Found in art books or photo catalogs. Very stiff, hard to fold repeatedly, and will cause the spine of the book to stretch excessively.
When looking for novels in thrift shops, feel the page thickness. If the paper feels like standard printer paper, it's perfect for your book folding project!