If you look closely at the end of the nibbler it has a slot in the black tip - basically, you put that into your panel (so you need a hole of around 1cm, or to be able to access the edge of the panel), then there is a small metal pin that moves up and down very quickly when you press the trigger, which cuts out a tiny half moon shaped slither of metal. Basically you just pull or push the nibbler in the direction you want to cut, just like drawing a slow line with a marker pen. Personallly, i've found it to be the neatest way of cutting smaller holes, but it really is down to personal preference, and that little air driven grinder is also very good.
Regards, Goops.
Edited by Goopster, 24 March 2009 - 09:48 PM.