First page Back Continue Last page Overview Graphics
Here's the same diagram, but for ffbb this time.
Take a good look at the three figures on the bottom left. They're all doubleface, but illustrate what happens when the threading direction changes. Most importantly, you get little gaps in the cloth surface where the weft can show through.
A common beginner question: "But why am I getting weft showing?"
Answer: because that's how doubleface works.