From the excellent advise here. this is my donut chuck. I still have to add screws for added safety.
This came out a lot better since I added the wood putty to the bottom of the nut before adding gorilla glue.
Looks good. YOu may find that you need another "doughnut" or two with different sized holes in them for different sized bottoms. I know I do. Anyway, you'll find lots of uses for this chuck in the years to come. 8)