An array of tools are needed to do the work of fine binding. To start with, I'll talk about paring knives. I have several knives and use them all regularly but I do have a favorite one. It is an English style paring knife made by my friend Jack Shapiro.
Jack made me this knife so I could teach him about leather binding. I had done two small quarter leather books while in graduate school so my knowledge about working with leather was limited at the time but I was all the Jack had. So when I said I did not have a paring knife I thought the tutorial would end there. A few days later he placed this knife down at my desk and asked when we could start. He also showed me how to sharpen and keep a good edge on it.
I taught him what little I knew back then and he pushed me to do more and helped focus me on the path for my work as a binder. Jack died several years ago but each time I use this knife think of him.
This is an English style knife with an angled edge. I use it for general edge paring. I also use French style paring knives with rounded blades. These work best for thinning out areas around head caps and smoothing areas when ridges can be felt along the pared edges of the leather.
Why two French and two English paring knives? At first I bought the second ones to see if there were other knives to recommend to students but as I used them, I discovered that there are differences with how they cut. I find there are times when one is better for a particular skin or for an area that I am having problems paring. Besides, you can never have too many knives.
To protect the edges of the knives I have made caps or cases for them. The caps are made from thin cardboard cut to fit around the blade and then covered in thin leather. The cases are made from layers of book board and are covered in book cloth and marbled paper. I make recessed areas with the book board so the knife sits down into the case and does not bang around, thus damaging the blade.
I also wrap my knives with leather to make them more comfortable to hold. It is a good way to personalize my tools.
This is my traveling set of knives. It hold two knives and a leather strop and is housed in a Japanese wrap around cover so it is easy to carry.
The strop has a piece of 600 grit wet dry sandpaper on one side and a piece of leather on the other side. There is a 5 mil. sheet of Mylar placed in between to keep the sand paper grit away from the leather and the polishing cream.
To keep a good edge on my knives, I have a leather strop and smaller strops covered with 600 and 1000 grit wet dry sandpaper in my studio. My leather strop is mounted to a piece of wood and has a working area of 10 x 2 3/4 inches. I rub Chromglanz Polishing Cream into the leather.
The sandpaper strops are mounted on pieces of book board. These are used when the edge of the knife has gotten too dull to be just stropped on the leather. The sandpaper helps to reshape and sharpen the edge and then the blade is stropped on the leather to finish polishing the edge.
Another important element in paring is the surface you work on. I have a small litho stone I use but I have also used marbled slabs. You need a very smooth surface to work on. Glass is not a good surface because it is harder than the steel the blade is made with and will dull the edge quickly.
A spokeshave used for woodworking is another tool that can be used in paring leather. The tool and the blade must first be modified for leather work. The angle of the sole plate needs to be lowered and the opening needs to be wider so the parings can be cleared from the blade. The blade needs a longer bevel and the corner has to be slightly rounded so they will not gouge into the leather. When it is used for leather, the blade is mounted backwards into the spokeshave. There is a good article written on how to modify a spokeshave in the Skin Deep newsletter from J Hewit and Sons Ltd.
There is also an article on sharpening the blade here:http://www.hewit.com/skin_deep/?volume=24&article=2#article
My spokeshave is from Sears and was bought back in the mid eighties. My binding class bought several others and someone agreed to reshape the soles for the group. When I first used it, things went badly. I had seen someone using it only once and it looked so easy. I put it away for years before I tried again. Later I realized that the sole just had to be reground to the new angle and the opening enlarged, but I also needed to finish smoothing and polishing the sole.
I tried many more times unsuccessfully to pare leather with it. I needed some help and started reading articles about how to use it and asked anyone I could how they did it. Slowly, I got the angle of the stroke and the depth of the blade right. It's fair to say that learning to use these tools takes lots of trail and error.