This is my home made station cradle aka sewing cradle. It's cardboard from leftover paper boxes and hotglue. Lots of hot glue. Iwould suggest that when buildingone of these not to use the cooler melting glue but the hot hot melt glue. It works much better.
I reinforced the bottom with tyvek so that my signatures would not fall through the bottom. I did this so that I could replace it. It's held with a couple of beads of hot glue on each side. Hte tyvek is then stretched tight over the bottom of the cradle. I think it seems to help the stations from flairing out too much.
It works for me. I'll be making one much larger for bigger books.