What is the precise role of alum in the sizing? Can I use rabbit skin glue instead of nigawa sticks?
I don’t know about alum. Some books on paper making may tell you, but my only paper making book is about making Japanese paper, and the word “alum” isn’t in the index. In the latest e-mail I got, the answer is: You CAN use rabbit skin glue to size paper, but it’s stronger than nikawa. It is hard to judge how much to use. It’s much easier to buy paper already sized from McClain’s in Portland, Oregon.