The folding machine is used to create 1 x 10 blocks that can be broken down to create 4 cube blocks and 2 cube blocks (the building blocks of the trusses).

Here is a YouTube video of the folding machine:
https://youtu.be/yx31IcRKIl4

Here is another YouTube video of the folding machine:
https://youtu.be/QkflN3ushr0