There is so much you can do with a plasma cutter. As mentioned previously, dry air is essential for expendable life and almost as important is shiney clean metal to cut on. Of course if the shiney metal has oil on it, it is VERY dirty! I am limited to about 3/8 inch steel with my unit so cutting nuts and bolts are not on my list. Sheet metal and flat stock (I include angle iron, and square rectangular tubing) are my mainstays. Small bar stock is also OK. Cutting expanded metal is a snap but does wear the tip a bit faster. A real time saving tool that will turn out very precise cuts.