Here is a photo of two lines of mechanical pencil evolution:
Two lines of mechanical pencil evolution. The first line, where the lead is advanced by by releasing a clutch with a clicker – refined to the side clicking pentel pd345. The pencils in that lines are as follows: 2mm lead holder, Eversharp clutch release pencil, pentel p225, pd345.
Then there are the “other” mechanical pencils. These twist from the side. They are perhaps the true analog of mechanical pencils, because they smoothly twist out the lead until it falls out, more or less an evolutionary dead end of mechanical pencils.
Until the Quill mechanical pencil.
The Quill is a twist type. But, it has a clutch release mechanism that limits how much lead you can twist out, and it has a digital feel to it – like the click pencil line. Furthermore, you can’t freely retract the lead by twisting the barrel the other way. When the Quill is twisted the opposite way, it locks, and you can push the lead in freely with your finger. Weird. Weird like a missing link.
Sorry, I couldn’t take it apart without breaking it. It seems the Quill corporation didn’t want me to know what was going on…
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