Pens and Pencils | Reviews and Data

What Is a Double-Knock Pencil?

Ohto Gripper Set
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Did you just see a “double-knock” mechanical pencil and have no idea what the name meant? Or why you would want the extra knock? Is this pencil some sort of postman who always knocks twice? (OK, rings, but you get the point.) This article should solve all your double-knock questions.

First of all, you should know that the button on top of a pencil or pen is sometimes called a “knock.” The act of pressing that button is sometimes referred to as “knocking.” So, by implication, you can probably guess that a double-knock involves pressing a button twice.

The double-knock is a two-step process where:

  1. The writing tip (usually known as a pipe) is extended from inside the pen
  2. The lead is pushed out of the writing tip

So the pencil technically has two types of knocks. Obviously if you have extended the writing tip (step 1) then any further presses will just advance the lead (step 2).

For our purposes we will restrict “double-knock” to pencils will a push-button of some kind. Some pencils, like the Rotring 600G, have a hidden pipe that can be revealed but it’s not don’t with a normal knock action. If you think of double-knock more in terms of a “double-action” pencil, then these other methods are certainly part of this category.

Why Double-Knock Pencils Are Popular

A double-knock clearly adds cost and complications to your pencil’s mechanism, so why do good pencils have them? The foremost reason is because it protects the pencil’s pipe and advancement mechanism. These two things tend to be A) pointy and B) sensitive, so hiding them away is almost always a good idea. Anyone who has experience a bent or broke lead sleeve (aka pipe) will understand the appeal.

Additionally, it looks cool! The blunt end of a double-knock mechanical pencil is a great look that many buyers flock towards it. It’s a nice change compared to the long, tapered tips found in most mechanical pencils. Additionally, the double-knock gives your pencil more a pen look, if that’s your preferred styling (or if you’d like your pen and pencil lineup to match).

Examples of Double-Knock Pencils

  • Pilot Automac
  • Pentel Graph Gear 1000
  • Pilot Delful Double-Knock
  • Ohto Horizon
  • Kuru Toga Advance

Vintage double-knocks:

  • Ohto OP-500
  • Staedtler Retro
  • Mitsubishi (various vintage models)
  • Mitsubishi Boxy (various vintage models)
  • Pentel Rolly (various vintage models)
  • Tombow Protect
  • Pilot ProTex HHK-300S
  • Pilot H-3003
  • Niji Grip 350

Non-button dual-action pencils:

  • Rotring 600G
  • Rotring 800 drafting pencil
  • Rotring 800+