Building chucks is far easier than I thought it would be, and im fairly satisfied. After looking forever for some I liked and never really finding a perfect set (with the exception of a woodalls custom pair) I found that chucks you build yourself you tend to perfer over those you buy.
Its really pretty simple dude, all you need a drill and some drill bits, and some paracord, poly-nylon cord(my preference) or chain.
You can use a dowel of wood purchased at your local hardware store, or you can use somthing like PVC. Even simpler, If you can find 2 matching wooden brooms or hammers etc. They will work well.
The hardest part of making nunchaku is the stringing process, which IMO the best yet is the Ernie Budo lab tutorial in this forum.
Im uploading my DIY's soon. be sure to check em out, If you like I can help walk you through building your own pair.
