My wife is a talented knitter. She collects yarn like I collect wood; you can never have enough of either! Sometimes she buys yarn that has been locally spun and dyed, then wound into skeins (around another cool tool called a niddy-noddy). A loose skein is of little use to her, so she needed a way to easily make loose skeins into a yarn ball. Enter the woodworker...
All the joints are tied with hemp cord, except where the bows attach to the hubs. This was done with fine gauge wire for durability and ease of attachment. The bottom hub rides on a fence, which tightens with a thumbscrew to lock in the setting.
In action, the swift bows and hubs rotate around that central pike, providing a convenient way to control a loose skein while it is wound into a ball. To use the swift, you also need a nostiprinne.
This is essentially a stick around which a ball of yarn is created. There are crank machines available that do this, but they are almost all made of cheap Chinese plastic, so no thank you. This takes a little longer to create a ball of yarn but it was made by me, on my spring pole lathe, from locally harvested wood.