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Author Topic: Lead in your pencil, how does it get there?  (Read 4447 times)

paul.fr

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Lead in your pencil, how does it get there?
« on: 24/07/2007 00:22:40 »
How do they get the lead in to pencils? Also, you can buy different coloured pencils. How do they change the colour of the lead?


 

Offline kdlynn

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Lead in your pencil, how does it get there?
« Reply #1 on: 24/07/2007 00:28:48 »
isn't it graphite and not lead? or am i crazy
 

paul.fr

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Lead in your pencil, how does it get there?
« Reply #2 on: 24/07/2007 00:31:09 »
isn't it graphite and not lead? or am i crazy

little miss clever clogs  ;) I shall start again:

How do they get the graphite in to pencils? Also, you can buy different coloured pencils. How do they change the colour of the graphite?
 

Offline kdlynn

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Lead in your pencil, how does it get there?
« Reply #3 on: 24/07/2007 00:33:07 »
i don't know. lol
 

Offline kdlynn

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Lead in your pencil, how does it get there?
« Reply #4 on: 24/07/2007 00:37:23 »
perhaps there are pencil fairies
 

another_someone

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Lead in your pencil, how does it get there?
« Reply #5 on: 24/07/2007 02:18:33 »
I don't think I have a pencil in the house to look at right now, but I somehow always assumed the pencils must be two halves glued together with the lead sandwiched between.

I was going to make a more puerile suggestion about putting lead in your pencil (maybe more pertinent to the pencil fairies), but thought better of it.
 

Offline kdlynn

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Lead in your pencil, how does it get there?
« Reply #6 on: 24/07/2007 02:38:38 »
actually i was thinking it was a hole drilled in the middle and the graphite... could it be liquid and poured in?
 

Offline kdlynn

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Lead in your pencil, how does it get there?
« Reply #7 on: 24/07/2007 02:46:37 »
or maybe heated just enough to make it stick to the wood. i really have no idea i'm just guessing
 

another_someone

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Lead in your pencil, how does it get there?
« Reply #8 on: 24/07/2007 04:00:17 »
actually i was thinking it was a hole drilled in the middle and the graphite... could it be liquid and poured in?

Melting point of graphite is about 3,600 Celcius - not something I would have thought to be very practical (in fact, the wood into which it is poured would not survive).

Another hypothetical possibility that occurred to me would be to run a high current down the core of the wood, causing the core to char - but that would not lead to a clear separation between the lead and the surrounding wood, and would probably not lead to a very straight lead either.

More pertinent probably is that I don't think that pencil leads are pure graphite, but rather clay mixed with graphite, and so it could maybe be poured or extruded down the core of the wood, and then kiln dried to form a solid mass.

http://en.wikipedia.org/wiki/Pencil
Quote
It was the Italians who first thought of wooden holders. An Italian couple in particular, named Simonio and Lyndiana Bernacotti, were believed to be the ones to create the first blueprints for the modern carpentry pencil for the purpose of marking their carpentry pieces; however, their version was instead a flat, oval, more compact type of pencil. They did this at first by hollowing out a stick of juniper wood. Shortly thereafter, a superior technique was discovered: two wooden halves were carved, a graphite stick inserted, and the two halves then glued together—essentially the same method in use to this day.
 

Offline eric l

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Lead in your pencil, how does it get there?
« Reply #9 on: 24/07/2007 08:37:25 »
They make no secret about it.  Go and check the site of Faber Castel, one of the world's leaders in the field at http://www.faber-castell.de/docs/index-news_asp_id~14978_domid~1010_sp~E_addlastid~0_m1~14376_m2~14404_m3~14918_m4~14978_suma~.htm
So, rather than putting the graphite into the pencil, they lay the graphite into a half pencil, and put the other half on top.
 

Offline kdlynn

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Lead in your pencil, how does it get there?
« Reply #10 on: 24/07/2007 10:25:28 »
i wonder how the two halves stay intact while sharpening
 

another_someone

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Lead in your pencil, how does it get there?
« Reply #11 on: 24/07/2007 12:45:07 »
i wonder how the two halves stay intact while sharpening

If they are using good glue, with the right characteristics, then I don't see why it should not stay together when sharpening.
 

Offline neilep

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Lead in your pencil, how does it get there?
« Reply #12 on: 24/07/2007 14:24:52 »
I luff to watch programs of incite, relevance and of International importnace.

One of the recent programs I watched  (How It's Made  http://en.wikipedia.org/wiki/How_is_it_made) was all about this company http://www.faber-castell.de/ and how they make pencils !...STOP PRESS !!!..I see that ERIC has beaten me to it  (three posts above).........suffice to say...it was a fascinating program and secures my standing as the life and soul within ' pencil production themed parties'

 

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Lead in your pencil, how does it get there?
« Reply #12 on: 24/07/2007 14:24:52 »

 

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