In several threads on Knockology, there are mentions about the more ubiquitous/white-label mechanisms, and now i’m interested to know more. So far, my knowledge could be summarised as follows:
• Schmidt mechanism - horseshit.
• Pentel P200 mechanism - solid, used in IJ Instruments.
Could someone list some of the other most common mechanisms, and in which pencils they’re used? Bonus points if you could explain why some are considered ‘good’ and others not.
Schmidt is not bad. Sometimes they are THE most sensible option when dealing with a ballpoint conversion. It’s just that it feels LAZY when a custom design is based around it, when no Parker type pen refill is involved in the first place.
The mechanism used in the Amazon double-knock and the Blick Premier Pro is the Kotobuki mechanism most famously found in the Kokuyo TZ-PSP3/5.
This same mechanism has been used in white-labeled double-knocks since its inception, appearing as Ohirra and also some unbranded pieces that occasionally show up on resale markets.
The Ohto Grip500 mechanism also appears in a TON of push-button-retraction pencils, including variants from Y&C, Niji, Platinum, Pyramid, Tomato, Linex, and others.
Cheers, Chris.
TIL there is an amazon double knock. Could you link that at some stage? I tried a few searches but came up empty-handed.
As far as I know, it’s not in production right now.
And it annoys the hell out of me that the 0.5 is accented with blue while the 0.7 is accented with orange 
I read your review just now. It’s pretty good looking pencil. Like the Rapid Pro and Uni Shift had a child.
I’ll keep my eye out for it.
Another pretty ubiquitous double knock mechanism is the one used in the Staedtler Retro, Rotring Rapid (not Rapid Pro), Alvin Draf-Tec Retrac, Platinum W-knock, and a bunch of asian brands I’ve come across. Some of them, like the Rotring Rapid, have an extendable twist eraser but the actual knock mechanism is the same.
I’ve really not had much problem to speak of with any of these mechanisms, but it depends on manufacturer. Some of the no-name pencils I’ve tried sometimes just didn’t work at all. But that was worse than usual manufacturing, not bad design.
Older continuous-twist mechanism pencils got jammed all the time and some of them really can’t be disassembled to clear them. If chunks of lead worked their way into the spiral guide that’s used move the propelling mechanism, and someone forced it hard enough, it wound up being deformed beyond recovery. I have several vintage Scriptos, Eversharps, and Parkers in that condition. Part of the problem was that pencil lead in the first half of the 1900s was brittle and broke super easily, but that mechanism also just had too many opportunities to jam.
Thanks Noah!