The pencil “lead” is actually a mixture of graphite and clay. More clay in the mixture makes the lead harder. A harder lead has a higher number. Pencils are numbered from 1-3 but most people use a ...

Common mechanical pencils come in sizes to accommodate 0.5, 0.7, and 0.9 mm leads, but there are bigger and smaller ones available. Perhaps one of those really large drafting lead holders could be ...

aka leadholders or drafting pencils, it releases the clutch – allowing you to decide exactly how much lead you’d like to advance. What is the difference between mechanical and clutch pencils?

Using 0.7mm leads for a slightly thicker line, the pencil comes in black or gold. The archetypal architects’s drawing tool, Staedtler’s clutch pencil was the ubiquitous drafting device in the days ...