Chris
In some thread, somewhere, we were talking about shading and I came to the realization that it
does make sense to shade your drawings with a pencil, as long as you realize you're only drawing the
effect you want and not the actual lines.
You also have to practice various shading techiniques so you can replicate on the metal the effect you drew on the paper.
I have, of course, come no where near mastering these things but at least I have a plan of action.