Walterjn That 1st one is the one I turned off after a couple minutes. He never shows anything about prepping the adapter or cleaning the tip after abrading. And he's fake from the fact that tip was not even epoxied on the shaft he pulled. Never follow those type examples. His shop is full of all the latest, most expensive tools...steer clear of this one!
And, yes, he would need a ton of shaft beads, as he used, after grinding the piss out of that shaft tip!! migawd. They are seldom needed, and best if never needed. It all depends on tip prep; also, all adapters are not going to be the exact I.D they should be. Some will be a hair oversize, from my findings of using 4 different types. But, they were never bad enough for bead use.
Only the totally uninformed would ever use JB Weld.