I also saw this a few weeks back and asked a question but got no answer. I'll ask again and maybe get lucky. 
Is that hammer-in chuck he's using something that is common? I'd never seen something like that.
Ray, I seen that done a few times at our woodturning club, they use an old type chuck, it has very little movement in the opening and closing of the jaws, and uses "C" spanners to operate the jaws. They leave the jaws closed tight and the wood a little oversized and just hammer it in. I personally don't like the method as although it's quick, I can never get it to run true and it can't do the headstock bearings any good. Just my opinion though.
Keith.
