The lead in your pencil ...

Factual Questions
1

Sorry guys, this thread has nothing to do with matters of procreation. This is a simple question for the industrial designists and other drawing persons out there.

Anyhow, I was doing some writing exercises with my 4yo son today and he asked me what does the “HB” on the pencil stand for?

Buzzzz, Dad is stumped and looks like a goose. Jeez, what’s he going to ask me in his teens?

Now I know that HB denotes the medium grade lead and harder leads are denoted as 2H, 4H etc. Conversely the softer leads are denoted 2B, 4B, 6B etc.

But what does the B stand for? What does the H mean for that matter? Please help or I’ll have to restrict him to using crayons.

2

B = Blackness [high graphite/low clay content]
H = Hardness [low graphite/high clay content]

HB means “hard and black”, being a compromise between the two qualities. There is also a grade ‘F’ between HB and H. I have no idea what ‘F’ stands for.

see http://www.berol.co.uk/pencil/index.htm

3

F = fine (in case you were wondering).

4

Much appreciated bibliophage.

I can now look my son in the eye and pretend I’m not such a big ignoramus!

Thank you :slight_smile: