The long and the short of it…
Int paper brilliant? When you ponder it, paper is pretty incredible stuff. It’s been with us for around 2000 years and I don’t doubt it will be with us for many eons to come. For most of that long history, paper has been made by hand. However, in the late 1700’s the first continuous paper making machine was invented. This continuous process introduced huge changes to paper; making it affordable and widely available but mechanisation also introduced another important change. It was a change Invisible to the naked eye and is still not too widely know about outside of bookbinding and printing; all of a sudden paper became anisotropic instead of isotopic; in short, paper got grain.
Grain? You mean like wood has grain? Yes! that’s exactly what I mean. The tiny fibres in machine made paper all line up in one direction, just like wood grain. This makes paper behave very much like a thin sheet of wood veneer too, allowing it to bend, fold or curl very easily in one direction but not so easily in the other. For bookbinders this invisible property of (machine made) paper is crucial.
In a perfect world, we bookbinders would like the grain in all the material used throughout a book to line up in the same direction; vertically, from head to foot. It makes for a book that is strong, covers that don’t warp, endpapers that lie flat and paste down easily. It gives us lovely floppy, easily-to-turn pages that won’t crack and fall apart quickly where they are folded and stitched and most importantly it gives us a nice, tight, smooth gutter.
A tight, smooth gutter… and no, that’s not a euphemism. When you open a book and look into the v shaped join between the pages, they should be even, flat and smooth on both sides. If you see that in a book, it tells you all is well in the world and the grain in those pages runs from head to foot or down the page from top to bottom. If, on the other hand you have a wobbly, crinkly gutter… ooh-err! The grain is running in the ‘wrong’ direction; across the page horizontally. The wobbling is caused by moisture in the glue on the spine of the book causing the paper to expand and cockle. Apart from looking ugly, it forces the pages and signatures apart making a weaker, bulkier book and it makes the pages hard to flip through. Having the grain the wrong way is not pretty and it’s not clever. If the question now on your lips is “how do I avoid an ugly gutter?” Then read on.
Choose paper with the grain running in the correct direction for your book. So, if you want to make and A5, portrait format, multi-signature book for example and you’re using folded A4 paper for the pages, then you would need the grain to be running parallel with the shortest edge of that A4 paper. This is known as short grain or grain short paper. (Conversely, if the grain of a sheet of paper runs parallel with the long edge, that is known as long grain or grain long). The same goes for endpapers. Make sure the grain will run vertically down the book when they are pasted in place and you’ll find them so much better behaved when you are gluing them down.
Now you know this, it should make your life easier… but for the fact that you’ll find the grain in most of the paper you go to buy runs the ‘wrong’ way for your project. You’ll find most A4 paper is long grain and most A3 paper is short grain. (A quick google or YouTube search will reveal many methods for finding out the grain direction on a piece of paper). It’s frustrating is it?
As a bookbinder I feel your pain, which is why the paper, board (and Bookcloth) we supply with our kits has grain that runs in the correct direction for that particular project; to make the process easier and the finished results more professional.
As well as our kits we also supply short grain A4 paper for bookbinding in lined, dotted and blank.