Book Conservator, Biblioteca Nazionale Centrale di Firenze
Curved polished needle. As I sew only for conservation purposes I always use blunt needles that I made through the years, even though I use a specific needle for every sewing structure I still think as this as an essential tool, the curved shape is a must for linked stitches and for in-situ reinforcements.
Pin vice. In most of my work instead of using awls I tend to prefer a pin vice mounted with a curved, pointed, blunt or straight needle.
Try square in steel. For most of my work I use my selfmade tri-square in solid steel with a brass handle, it is useful both for cutting and scoring purposes.
Stanley 28-109 slim knife. I have many other knives around, some that I made and some that I bought, but most of the time my hand reaches for this one first.
Ivory folder. I made it from the handle of a kitchen knife that I bought at an antique market, even though I like to use more modern tools I think that my hand is used to it more than others, I polished it with micro mesh to 12000 grit and this make it very smooth thus leaving very little marks on the surface. The firmness compared to the teflon folder makes it more durable and its pointed shape reaches for every corner.
What I would still miss a lot, depending on the size of the book are: brushes for adhesives, tweezers for delicate work, a proper awl, if there is some wood involved my low angle block plane, if there is paring of leather involved my self made paring knife and my Stanley modified spokeshave. But I have to say that most of the paring work happens in rebinding work that I try to avoid, though this is not always possible.