Naked Science Forum

General Science => General Science => Topic started by: cuso4 on 04/11/2004 20:26:45

Title: Pencil lead
Post by: cuso4 on 04/11/2004 20:26:45

Hello~ I haven't been around for ages...the amount of work to do has got on top of me.

Anyone knows how pencil lead of different hardness (eg. 2B, B, HB....etc) are produced? I say hardness of pencil lead because if it's softer then more graphite will be left on the paper. Is this due to the % compositions of graphite in pencil lead? What other substances are also in pencil lead?

Angel

Title: Re: Pencil lead
Post by: moses lawn on 05/11/2004 06:51:55

The graphite is mixed with various proportions of clay to give different hardnesses of pencil leads.

Title: Re: Pencil lead
Post by: cuso4 on 06/11/2004 13:58:46

thx moses lawn

Angel

Title: Pencil lead
Post by: rosalind dna on 15/01/2008 17:25:14

This has the whole range of the different hardnesses of pencil leads, which
is made out of graphite. Formed from clay or charcoal products as these links
will tell you, I hope.

http://en.wikipedia.org/wiki/Pencil
http://www.studioarts.co.uk/links/hintsandtips/graphicsinformationpencils.htm