I know. It's a small thing. And I still get a kick out of it.

A few years ago I acquired an old Atlas metalworking lathe. I've not used it a lot, but when I do, it's a kick!

Need a 5 mm brass tube?

Don't have one?

Concentrically bore a 5 mm brass rod.

Try that with your hand drill or drillpress. (I don't think so!)