Mechanical Keyboards 101: Part One – What they are and where they came from

Posted: March 23, 2017 in keyboarding

A long, long time ago, in the 80’s:

In the days of yore, when dinosaurs walked the earth and the keyboards that were included with a computer were actually considered to be important, keyboards were better than they are today. The technology that was employed in said keyboards was the topic of some conversation in the design meetings. Yes, the computer manufacturers anticipated that we’d like to actually employ the keyboard they sent along. For typing, to be clear. Not just to catch crumbs from our hastily-eaten meatloaf sandwich during our twelve minute lunch. Ah, the good old days.

What was the difference between those old keyboards and the ones you see included now? What made them better? Why did computer manufacturers begin using sub-standard materials and engineering for an integral input device that we still use? Hark, I shall discuss these topics. At length. What keyboards were, what they are, and the functional differences between the good stuff and the junk.

The Difference:

The first and most important difference between old keyboards and new was the way in which they were constructed. In old keyboards, the mechanism was mechanical in nature, where the new keyboards use a fairly simple methodology for key press registration.

In a mechanical keyboard, from the present or bygone era, each key operates with its own self-contained machine. Below each key, there is a discreet mechanical switch of some kind. That is the “mechanical” in mechanical keyboards. Of course, all keyboards are mechanical, if we consider the most basic definition of the word. They have moving parts. The difference is the method by which the signals are created that send the keystrokes back to your computer, as well as the complexity of said method.

How a Rubber Dome Keyboard Works: 

In a modern scissor-switch or full stroke keyboard (laptop vs. desktop style), the resistance you feel as you press the keys is from a rubber dome. As the dome collapses, a contact is made with a tracery of electrodes, and the keystroke is sent. Below the key caps, there are apertures where the stems stick through the base plate, and a mesh of rubber membrane “domes” is glued onto a grid of switches. If the elements that make up this matrix happen to fail in some way, there’s not much you can do. Everything is, in some form or fashion, hooked to everything else. There’s no way of repairing a serious problem. Perhaps you can replace a broken key cap, but that’s the extent of it. I’ll have a lot more to say about rubber dome switches as we go along, but that is the short version.

How Mechanical Keyboards Work:

In a mechanical switch keyboard, each switch is basically its own thing, and a new switch could be plugged in, provided that you wished to crack the case open to do so. When I say “plugged in”, that probably entails a bit of work with a soldering iron, just for clarity’s sake. In this more discreet design, there is a small collection of parts below each key. These are typically, from top to bottom, as follows:

1) The key stem. This is the part that the key cap interfaces with. It acts as a plunger that moves downward and enacts the key press.

2) The chassis of the switch. This holds all the bits and parts together. The key stem travels down into it as the key is pressed.

3) A spring mechanism. The spring tension can be created with a few different types of device. Most often, it will be a very small coiled spring. Leaf springs are also used at times. Some discreet switch technologies will use a rubber dome as part or all of the resistance methodology. An interesting, but essentially moribund type of keyboard switch was the dome-and-slider mechanism, that worked in this way. The “hybrid” switch of today is the Topre switch. I’ll have a whole article on this design at a later date.

4) The instrument of tactility/click. Not all switches employ this feature, but those that do will have some part or parts that allow the force curve of the spring pressure to be altered at some point in the key travel. If a switch is to have a click as it engages, the creation of this sound will bear upon how the switch internals function. Most clicking sounds a keyboard switch makes will be caused by the spring hitting against the chassis of the switch housing, or something similar to that. This noise is not to be confused with either the noise of the key hitting the base plate (bottoming out), or the key reset sound (a resonance or chatter that the switch exhibits when it comes back to the top of its travel under spring pressure).

5) The switch itself. All of the moving parts allow us to, with at least some accuracy, press the correct keys at the correct time. When a key is pressed, the key designer decides at which point in the key press the switch registers the event. This is most often done by completing or breaking a circuit in the bottom of the switch. In the bulk of switch designes, it is a membrane that is manipulated by direct contact with the switch’s internals, physically being opened and closed by the key action. The switching can also be done via Hall Effect, capacitance, or optical sensor. There are probably even other, more esoteric methods for sending the electronic signal. The wiring schematic of the switch and the inclusion of diodes or particular circuit designs can sometimes alter the way keyboards react to more than one key being pressed at the same time. This is typically not of import to the typist, but gamers will often find it necessary to mash several keys at once, and not lose any of the inputs. This quality is often referred to anti-ghosting or n-key rollover. (Sometimes some number, rather than n, if the number of keys is finite.)

Compare and Contrast:

The full membrane, rubber dome technology that has been widely used in recent years is doing all the same tasks, it is just a much, much simpler device with far fewer parts. Complexity being the enemy of economy, it has proven that “good enough” is often the popular choice. Mechanical keyboards, in those same years, have fallen by the wayside. I don’t know of any mainstream PCs that include them as part of their packaged equipment. I will attempt to illuminate the reasons why, and the arguments both for and against mechanical keyboards in the rest of this article. Let’s dig into it.

Rubber Dome vs. Mechanical:

Will both technologies work? Yes. There are some quite good rubber dome keyboards. They are far easier to produce than a fully mechanical design, and the technology can function pretty well, provided that other elements of the keyboard are well thought-out. Rubber dome keyboards can also be made far thinner, so that they can be used in space-conscious implementations, like laptops. While it would be possible to put a scissor switch (like on a chicklet keyboard) atop a mechanical switch, it would still yield a deeper, less compact form factor. There are low-profile mechanical switches, but they have rarely maintained the qualitative advantages that are the hallmark of their larger peers.

Not all mechanical switches have been good. Far from it, some of them have had average or even poor typing dynamics. Most of the switch technologies that have managed to survive through the lean years of rubber dome dominance are at least passable, but some are, at least to the average typist, no better than a run-of-the-mill stock keyboard. Much of this is also personal preference, and intended purpose. A gaming keyboard has different requirements than a pure typist’s tool, and so a particular switch might be great for one, but not that amazing for another.

The hands that sit on the keys are also a large component in this equation. We develop skill with a keyboard. All its quirks become known to us. The spacing and feel, the necessary key travel and force, the sound, the layout. If you’ve done a great deal of typing on a particular sort of keyboard, you’ll be a little better on that keyboard than on others.

Mechanical keyboards have a particular feel. In the first minute, or hour, or even week, you might find that it’s harder to type at the same pace and with the same surety as it might have been with your old keyboard. Even if the new one is lauded as being the cat’s whiskers, and the old one was a steaming pile of crap. Before familiarity sets in, we can really struggle.

I typically may see six, eight, even ten keyboards of all different types through my work day. Laptops, desktops, wonderful mechanicals, deviously unpleasant pieces of junk…you name it. That means that I have my moments of seeming futility on any given ‘board. My brain has to re-map. A lot. That’s just something you have to expect. If you get a mechanical, don’t expect that it’ll be the best thing ever for the first few hours, at least. Give it time.

The Mechanical Advantage:

Old, vintage keyboards had more than just their complex design going for them. They also had crazy build quality. If you look back at the time when computers cost far more (in the dollars of the day) than they do now, the quality of their peripherals was held to a higher standard. After all, the peripherals were the “touch points” for the computer.

No one wanted to spend what they could use to buy a luxury car on their new IBM PC, only to have the keyboard be terrible. Remember, also, that IBM, the first giant of home computers (in the US), was the maker of one of the greatest typing machines ever invented, the Selectric typewriter. In the business world, these were the undisputed, heavyweight champions of typing. They were expensive. They were indestructible. They provided a superb typing experience.

When designing their computer keyboards, this long expertise on the part of the manufacturer led them to pay some attention to what typing on these early computers was going to feel like. It was important to them. It was their brand. IBM, after all, stood for International Business Machines.

Beyond just the typing feel, these devices were built to last, to suffer though a huge amount of use and abuse without falling apart. Some of the keyboards I’ve had the misfortune to experience in my day job, that of a computer tech, have been so poorly manufactured as to be almost useless.

Let’s talk about the worst keyboards for a moment. What was it that made them so bad? Weren’t they just like any of the other examples of the breed? Sigh. Yes, they had the letters and numbers on them, but beyond that, they were utter trash. Some worked great when first taken out of the box, but they would wear very oddly, such that some keys would have wildly different levels of pressure to actuate than others. Some would go right to mush if people used them with a purpose. After a few months of heavy typing, they would have all the feel of typing on small squares of rancid Jell-O. Some had such sloppy or sticky keys that just getting a sentence out with out dropped characters seemed impossible.

In a business environment, where many people are using the computer all day long, they suffer far greater and faster abuse than anything a single home user might inflict. In this higher duty cycle, any flaw in a device will be shown with cruel certainty. In these roles, modern keyboards are a commodity. They are assumed to be replaceable parts. Some of the switches on old keyboards from the golden age were tested and guaranteed to be able to survive over one hundred million key presses. So, yeah, change in philosophy there.

Remember, too, that the typists of the day were there at the computer to create work product. There was no mouse. There were barely any games. This was serious, and it was assumed that people would be sitting at the PC for hours, creating a great deal of text entry. In our modern implementation of the computer, we are more passive, in many cases. We work in a graphical user interface. We have a mouse or similar pointing device. We often sit for long stretches, just experiencing whatever we’re reading or watching. I’ve seen a lot of people who, other than inputting their password and perhaps fumbling a few one-line comments onto a social media site, could very well do without the keyboard altogether. After all, isn’t that what tablet computers are all about – we simply do the minimum to get where we’re going, then become passive observers.

There are a good many of us, however, who still use the keyboard extensively. We’re the sort to create thousands of words of text in the course of an evening or a work day. The purpose of this text could be anything, but if we’re using a sub par keyboard, it can be painful and un-fun. My feeling: everyone deserves a willing dance partner. My answer to having such a partner is to find the correct mechanical keyboard for you, and to allocate a little discretionary income toward that purchase.

In the next episode: 

Mechanical Switches in the Modern Day

Cheers, and Happy Typing!

  1. […] Mechanical Keyboards 101: Part One – What they are and where they came from […]

  2. Alex says:

    You really make it seem so easy with your presentation however I in finding this topic to be really one thing which I feel I would by no means understand. It kind of feels too complicated and very large for me. I am having a look ahead to your subsequent put up, I will try to get the grasp of it!

  3. Alex says:

    I am no longer positive where you’re getting your info, but great topic. I needs to spend some time studying much more or working out more. Thanks for wonderful information I was searching for this information for my mission.

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