During the manufacturing process the pencil lead is threaded, as is the bore of the wooden pencil casing.

This allows the lead to be screwed out of the casing in the event of the break. The tip of the pencil, which is the only mechanical part of the invention facilitates this rotation by being capable of rotation itself. Simply place tip of pencil between index finger and thumb to turn.

The wooden casing needn't ever be replaced and can be oranately carved and painted to suit the user's preferences. Replacement Screw Lead can undoubtedly be purchased if one is so willing and able to do so.

The replacement lead is slightly longer than the pencil casing and is manually screwed into the opposite end of the pencil as the twistable tip. Once it is screwed in far enough to be engaged by the twistable tip, the tip can be twisted to screw it the rest of the way.
-- cuckoointherye, Jan 29 2005

A vertical view pencil lead. http://photobucket....v636/cukoointherye/
Where A represents overall diameter; B represents pencil core; C represents depth of thread. Pretend that every quadrant is symetrical to the next. [cuckoointherye, Jan 29 2005]

Can it be sharpened?
-- bristolz, Jan 29 2005


it is sharpened via a small conical cap that is placed atop the exposed led, which grinds it to a point. It can also be sharpened by rubbing it against a coarse surface.
-- cuckoointherye, Jan 29 2005


Not sure how this is functionally different from a mechanical pencil, the kind draftsmen used to use before autocad. Is it just that the threaded lead is cuter?
-- robinism, Jan 29 2005


A drafter's pencil is the best pencil in the world. It combines the durability of a wood pencil with the easy lead replacement of mechanical pencils. I don't use anything else.
-- Aq_Bi, Jan 29 2005


Oh I beg to differ Ian. A drafter uses only the tip of his pencil and holds it completely vertical. The core of the pencil, which is shaped to point, will not be affected by the threading. As for discomfort of use, drafters seem to get accustomed to it.
-- cuckoointherye, Jan 29 2005


The threading will not be so deep as to interfere with the cross section of the lead. A quick diagram will be linked shortly
-- cuckoointherye, Jan 29 2005


I think [robinism] put it well. A mechanical pencil (also called a propellor pencil, I think) is better, but this is cuter.

Problem to solve: you have been using the pencil for a when the lead breaks a couple of mm up inside. How do you now turn the thread when you can't get a grip on either end?
-- wagster, Jan 29 2005


Good problem. Your problem is based on the fact that lead is fairly brittle. And so is the solution: the solution is to sacrifice the entire piece of lead by shattering it and banging out the contents. This makes me think wood is not the best substance - I just like wood.
However, as long as the lead is threaded into the twistable tip it can be turned. Problem makes me think that the easiest way to insert the lead would be to put it in the end with the twistable tip by reversing the direction of the turn.

-- cuckoointherye, Jan 29 2005


Shattering the lead when it's fully supported by the wood sheath (or any other material) isn't going tobe possible
-- scubadooper, Jan 29 2005


Not if the material is slightly flexible. Like a semi-hard plastic... and whats with the rigorous examination here, this is a halfbaked idea. If it was worth anything I wouldn't post it.
-- cuckoointherye, Jan 29 2005


The idea is worth something - it's worth discussing. So we're discussing it.
-- robinism, Jan 29 2005


If you insert a long jewellers screwdriver into the hole, you could probably get enough purchase to unscrew the errant piece of lead.
-- wagster, Jan 29 2005


Use a corkscrew to push the lead out.
-- Ling, Jan 31 2005


My pencil has an eraser which works something like this. That is, you turn a section near the tip of the eraser, and the eraser extends. There are more parts -- a threaded tube, a smaller tube with slots in it, and a little shuttle which pushed the back of the eraser -- so it's not quite as elegant. It doesn't require a threaded eraser though, which probably makes for cheaper refills.
-- tiromancer, Jan 31 2005



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