I've made a few of these, and it seems like the fit can be different from kit to kit. But it's still one of my favorite wedding pens.
I've turned a few kits where the bands or end pieces have raised bands themselves. Often, the bushings are not quite sized right for a proper fit of blank to pen, as the bushing size doesn't account for the fact that the kit parts have little raised bits themselves, and are just sized for the maximum diameter of each kit part.
I've taken to putting the turned blank directly between centers, and turning them down a bit more. I'll often measure my diameter just inside the raised bumps, bands, whatever on the kit parts, where the diameter is smaller. The one challenge with that, that I've found, is if you aren't careful, or choose a diameter that is just a bit too small, then the blank can get very thin and crack or chip more easily. Still, I prefer the bands on the kit parts to be larger than the diameter of the blank.
