I've been wanting a sketchbook with a variety of paper in for a while, rather than just the same kind of paper throughout. Since I can't find this type of book anywhere I finally decided to make my own.
I made a simple single signature sketchbook with a cover of stiff cardstock - it's not very complicated to do. I cut the papers I wanted to size and stacked them neatly, keeping them together with clips. I cut the cover to the same height but ½ cm wider to protect the edges of the pages, scored down the middle with a blunt paper knife, and marked where I wanted to punch holes for sewing.
Here are the stacked pages clipped onto the cover and marked for punching. I used my old dry point needle to make the holes:
I placed the sketchbook on a folded blanket so I could push the needle right through - you can see how the holes pass right through the cover here:
The thread I used for sewing is a strong waxed thread laid double. I punched five holes in the spine and started in the middle one - I will make a diagram if anyone is interested:
Now the book is being blocked under a stack of heavy books - I'm leaving it there for the next 2-3 days and hoping it will then stay closed. I forgot to fold the papers of the signature individually first so it might take a little longer than it would otherwise have done, but I'm counting on it not making any difference apart from that.