What does "Mechanical" mean?

[msiegel]

Our beloved mechanical keyboards have only one thing in common...

Something that "other" keyboards don't have...

Metal springs

True, or false?

[wellington1869]

the way we've used the word "mechanical" on gh, it seems like all we mean is "does something different from logitech and microsoft"

maybe metal springs is the only common factor?

[rdh]

False, I'd say.  

I draw the dividing line between switches that require bottoming out (rubber domes and other more or less pure membrane boards) and those that don't, though I suspect not everyone will agree.

Which could be taken as another way to say "does something different from logitech and microsoft", I suppose.  :-)

For example, I have an old Key Tronic here with buckling sleeves and capacitive switches, but I consider it mechanical.  It has but one spring, which is on a key that's intended to be harder to press than the others.


EDIT: Removed extraneous word.

[timw4mail]

Bottom out makes sense, but I like to think that each key has an individual switch, as well.

Although it's kind of a gray area with the membrane Buckling springs, this seems to me to be the most differentiating factor of "mechanical" keyboards.

[rdjack21]

I think the no Bottom out option is the best. You can't really say individual switch because even crappy rubber dome boards have a individual switch on each key (its the dome under every key). But even on the the Bottom out type of boards there are a few that are decent to type on.

[rdh]

Bottom out makes sense, but I like to think that each key has an individual switch, as well.

To me, the switch is the electrical contact - the thing that shorts the row trace with the column trace.  (I have a pretty literal mind.)   In that sense, membrane and rubber dome boards do have switches and capacitive keyboards don't (excepting the DIP switches), which is why I draw the line where I do.   (I'm a Topre fan, wouldn't want to exclude my own favorite. :-)

What I think you're saying is that each key is built out of it's own individual parts (beyond the key cap and maybe a plunger). Is that more or less it?

[quadibloc]

In the old days, a keyboard was "mechanical" if it didn't involve a non-mechanical step in the key action.

So a Hall-effect switch wasn't mechanical, because it used an electronic chip to detect a magnetic field. Capacitative switches would also be considered electronic, since you needed electronics to generate the high frequencies used to measure capacitance. A reed-relay switch would be a borderline case.

Both of those, of course, had metal springs to return the keys back to position.

And, by this criterion, a rubber dome contact switch would be mechanical. But the first touchpanels were capacitative. Still, one usually thinks of something as "mechanical" more readily if it has metal moving parts, like an alarm clock... or a Cherry or ALPS switch.

So the term "mechanical", as it is now used, is something of a misnomer. The main distinction between the switches called mechanical, and those that aren't, though, could well be the metal springs these days - because flexure in a rubber sheet leads to much shorter life than flexure in a metal spring, 10 million instead of 50 million keypresses.

So one has the rubber dome switches at the short lifespan end of the spectrum, mechanical switches in the middle, and the older expensive (but not tactile) technologies like reed relay and Hall effect provide the longest lifespan.

[itlnstln]

When I first joined GH, a lot of us at that time suggested that the BS assemblies (both M and F type) were not true mechanical switches since they do not make a mechanical connection to send a signal. The same could be said for Topre switches. Personally, I try to avoid the term "mechanical" when describing good keyboards since you tend to get people on either side of the fence arguing that a particular switch is or isn't mechanical (along the lines of what quadibloc said). I try to use "quality" instead of "mechanical" since it's not as specific.

[lowpoly]

Every switch is "mechanical". The only non-mechanical keyboards I can think of right now are those laser phone keyboards. Edit: and all those on-screen variants.

As soon as you move away from this it becomes a matter of definition.

Here on GH, at least a year ago - like itln mentioned - it was a code for switches with metal to metal contacts.

[ch_123]

To me, a 'Mechanical switch' is one of the three main types of contact mechanism - each key has it's own self contained electrical switch, and depressing it causes two metal electrical contacts to come together. This is in contrast to a membrane or capacitive keyboard.

But yes, I'd also use it in reference to what would be better referred to as 'High quality' keyboards.

[cmr]

i would define the term as follows.

mechanical keyboards include those which employ individual moving assemblies in which two conductors make a physical connection to complete a circuit, thus signaling to the keyboard controller that a key has been pressed.

the term is also applicable to designs which utilize mechanisms to provide haptic or aural feedback, even when there is no mechanical contact utilized in the circuit.

[rdh]

Personally, I try to avoid the term "mechanical" when describing good keyboards since you tend to get people on either side of the fence arguing that a particular switch is or isn't mechanical (along the lines of what quadibloc said). I try to use "quality" instead of "mechanical" since it's not as specific.

Yeah, that makes a lot of sense.

Not all mechanical key mechanisms are acceptable (e.g. the "Mechanical Touch" buckling spring boards have a pretty low reputation), and not all rubber-dome boards are made of concentrated evil.

As I admitted above, my definition is partly drawn so as to keep my current favorite key type on the "right" side of the fence.   (I came up with it while trying to classify a certain cheap-but-clicky board I bought in a thrift shop.   Still gotta post about that one.)

[lowpoly]

mechanical keyboards include those which employ individual moving assemblies in which two conductors make a physical connection to complete a circuit, thus signaling to the keyboard controller that a key has been pressed.

That would include every rubber dome but exclude the Model F.

I think the 'contains metal spring' suggestion from the OP is quite clever, even if it includes a few variants that would be frowned upon here. Like the C64 keyboard for ex.

[cmr]

i guess the membrane layers are technically moving, but they are not individual assemblies.

[huha]

That would include every rubber dome but exclude the Model F.

I think the 'contains metal spring' suggestion from the OP is quite clever, even if it includes a few variants that would be frowned upon here. Like the C64 keyboard for ex.

... and the beloved Fujitsu Peerless.

I'd go a step further and like to demand the spring has to actually be part of the key action. The Topre spring is mainly just there to change capacitance.

-huha

[ch_123]

What about rubber dome boards that use some sort of slider between the key and the dome?

[Rajagra]

I would like to say that a mechanical keyboard is one where the switches are engineered; designed to register a keypress in an efficient manner.

As opposed to lowest common denominator keyboards which are included almost as an afterthought, matching the way they are designed primarily to be cheap and the method of registering a keypress also seems to be an afterthought or lucky coincidence.

It may not be a literal definition, but it's how I like to think of it.

[timw4mail]

With the exception of the Buckling spring mechanisms, I would define it as a keyboard that contains high-quality individual self-contained keyswitches, that offer some sort of quality and comfort advantage over a traditional keyboard.

Or in general, a keyboard that has better feedback and reliability than your run-of-the-mill keyboard.

[msiegel]

What about rubber dome boards that use some sort of slider between the key and the dome?

hmm... on one hand you might not have to bottom them out...

but on the other hand they don't have a metal spring

by my criterion, they're not "mechanical"

[msiegel]

Mechanical means expensive.

hey, i bought a model m mini for $8

it was a fixer-upper

[itlnstln]

My definition is similar to that of quadribloc's (if I understood correctly).  To me, "mechanical" means a metal to metal contact.  Thus, Alps, Cherrys, SMKs, Mitsumis, etc. are mechanical.  Rubber domes, membranes, capacitives, etc. are all "electric" switches.  Thus, BS, Topres, rubber domes, etc. are not mechanical.  Neither definition assumes a particular quality-level.  Either can be excellent or crappy.  I, personally, focus on "quality" keyboards than a switch definition.

[Rajagra]

How about this straight definition of mechanical: "done by machine."

In cheap and nasty keyboards the user pushes parts together and simple proximity creates the electrical contact which results in key recognition.

In mechanical keyboards the process is indirect: you provide force to a simple machine - a set of linkages, levers or whatever - any piece of engineering that actively governs the progress of movement and determines when actuation takes place.

[timw4mail]

How about this straight definition of mechanical: "done by machine."

In cheap and nasty keyboards the user pushes parts together and simple proximity creates the electrical contact which results in key recognition.

In mechanical keyboards the process is indirect: you provide force to a simple machine - a set of linkages, levers or whatever - any piece of engineering that actively governs the progress of movement and determines when actuation takes place.

In other words a mechanical switch is a switch with a length-reducing leverage assembly. That definitely makes sense.

[msiegel]

you guys are brilliant, i'm glad i posted this question

[msiegel]

say... that would also mean that IBM models M and F *are* mechanical:

their spring/hammer assemblies act as levers to press the membrane switches