Sewing frame H key

Continuing my trend of bookbinding tool parts, an H key for a sewing frame. You need a few of these if you want to bind books with tape.

Ignore my previous suggestion of chipboard, it's a lot of work for a key that won't last very long. I tried quarter inch oak, but that splits too easily along the grain, I might upload some pictures later, but trust me, it doesn't work. I bought some quarter inch pine plywood, I'll see how that works when I have some time.