Michael Horowitz wrote:
I want to mark sheetmetal for bending.
Can't use a scribe because I'll weaken the metal.
Magic Marker is too thick.
Pencil doesn't show.
What do you use? - Mike

I use a fine point Sharpie, me, but I get annoyed when they dry out.
Before Sharpies, there were metal marking pencils, developed for just
this purpose, with non-corrosive pigments. You can still get them:

http://www.office1000.com/discount/pencils-marking.html