When your knocking up a pallet of window frame and you accidentally slip your peen into a nail hole and hammer it down. Mostly are joiners. If you need to know what a joiner is ask Nedklaw.
Me: aye up son how was work
Wood bummer: good son
Nedklaw: what you do?
Wood bummer: I’m a joiner
Nedklaw: what’s a joiner? what’s one of them then?
Wood bummer: let’s just say I have a lot of splinters in my one inch wonder son
Nedklaw: why’s that?
Wood bummer: well you know what they say about wood bummers!