Nice, cool stuff. High school hand drafting taught me a lot about the practical differences between hardness weights and their uses (e.g. center lines may requi

Nice, cool stuff. High school hand drafting taught me a lot about the practical differences between hardness weights and their uses (e.g. center lines may require different weight than dimensions; can't remember specifics at this point). This page goes into much more detail beyond drafting as it's the page for "pencil".