When both hinges are damaged or broken, the crash must be replaced before the text block is reattached to the case. Cut or tear through any of the crash that is still attached in the hinge area. If the endpapers need to be replaced or repaired, do those repairs first. Clean the spine. Remove the old crash and any paper liners that come off easily. If the book is sewn, take-care not to damage the sewing threads. Remember, it is not essential to…