Editing Keycap mount

{{TODO diagram|reason=Would be nice to have diagrams of each mount with dimensions}}

A '''keycap mount''' is the interface between a [[keycap]] and a [[keyswitch|switch]].
Some mount types are standardized between switch and keycap manufacturers.

==Integrated mounts==
A mount is "integrated" when the bottom part of the keycap is the switch mechanism's primary slider. Integrated mount is not a standard: integrated mount keyboards are not incompatible with each other.

*The majority of full-travel [[rubber dome]] keyboards. The exceptions are few.
*[[IBM buckling spring]] keyboards without "two-piece" keycaps, and non-alphanumeric keycaps on two-piece keycap boards
*[[IBM Model M2]]

<gallery widths="250" heights="150">
File:IBM Model M -- one-piece keycap.jpg|IBM one-piece buckling spring keycap ([[caps lock]] from a 1996 [[IBM Enhanced Keyboard|Model M]])
File:Dell integrated mount keycaps.jpg|Dell integrated mount [[rubber dome]] keycaps
</gallery>

==Snap-on mounts==
Snap-on mounts have flat-topped sliders onto which the keycap is affixed. Snap-on mounts are all proprietary and are not compatible between keyboard types.

'''Examples:'''

<gallery widths="250" heights="150">
File:IBM Model M -- two-piece keycap.jpg|So-called "two-piece" [[IBM buckling spring]] keycaps (snap-on keycap over a stem, or slider)
File:IBM Model M -- two-piece keycap mount, front.jpg|Front view of same
File:Fujitsu FKB4700-152 -- snap-on keycap.jpg|[[Fujitsu Peerless]] slider and keycap
File:Alps ultra low profile -- keycap mount.jpg|[[Alps ultra low profile]] keycaps
File:NMB Hi-Tek caps.jpeg|[[Hi-Tek Series 725]] keycaps
</gallery>

==Cherry MX mount==
[[File:Cherry_MX_blue_closeup.jpg|200px|right|thumb|Cherry MX switch and its mount]]

A cross-shaped stem on the switch's slider into a cross-shaped hole within a cylindrical stem in the bottom of the keycap.
This is often called a "Cherry MX mount" because it is found on [[Cherry MX]] switches.
Whether the mount type has an industry-wide designation is unknown.

Cherry's MX keycap specifications give the keycap slot dimensions as a cross 4.1+0.05 mm wide, with arms 1.17±0.02 mm wide<ref>[[File:Cherry MX 1×1 keycap specification (1983).pdf]]</ref> (this would make them 1.465 mm long). There are no known specifications for the switch stem.

[[Signature Plastics]] gives the dimensions (presumably of the keycap) as a cross 0.159ʺ (4.04 mm) wide, with arms 0.047ʺ (1.19 mm) wide.

[[Cherry M8]] switches use a cruciform mount with the same lateral dimensions as MX switches, but with a shorter switch stem. This shorter stem leads to keycap incompatibility. Cherry produced a [[Cherry MX-M8 Adapter]] variant of the [[Cherry MX]] switch family which allowed the use of shorter M8 keycaps on otherwise standard MX switches.

See: [[:Category:Keyboard switches with Cherry MX mount|keyboard switches with Cherry MX mount]]

===Switches===

*[[Cherry MX]]
*[[Cherry MY]]
*[[Marquardt Series 6184]]
*Some [[Mitsumi miniature mechanical]] switches
*[[:Category:Clones of Cherry MX switches|Cherry MX clone]] switches
*Some [[Futaba clicky switch]]es
*Some Gateway keyboards, including early [[Gateway AnyKey]], Model no 2189013-XX-XXX
*BTC Dome with Slider

... and more

===Keycap manufacturers and vendors===
Additional keycaps are made/sold by:

*[[Signature Plastics]]
*[[WASD Keyboards]]
*[[Devlin]]
*[[Tipro]] (low profile and relegendable)
*[[Jarltech]] (low profile and relegendable)
*[[Genovation]] (low profile and relegendable)

... and more

===Notes===
There are also some mount types that are quite similar but not exact like the Cherry MX mount.
There are switches with a cylinder around the stem, and there are keys with struts in-between the keycap stem and keycap wall that make it not "Cherry compatible" without modification.

==Hirose Cherry mount==
Hirose Cherry mount is a smaller cross than Cherry MX mount. Cherry MX keycaps will fit on Hirose Cherry switches, but Hirose Cherry keycaps will not fit on Cherry MX mount keycaps. The horizontal arms are shorter but approximately the same thickness, but the vertical arms of the cross are noticeably thinner, and keycaps made for this mount won't fit onto a Cherry MX mount keycap.

==Custom cruciform==
{{Main|Cross mount clearinghouse}}

There are many keycap mounts that look very similar to Cherry MX mount, but have incompatible dimensions. They will not take Cherry MX keycaps. Such mounts include those of [[Cherry M6]] and [[Cherry M7]] switches. The slider dimensions are not always 90° rotationally symmetrical: one pair of cross arms may be thicker than the perpendicular pair of arms.

==Tee and bar mount==
Numerous switch types have tee (⊢) and bar (|) mount sliders. Such switches typically take cross-mount keycaps, and as such, the switches support full 90° rotational symmetry. For example, the [[Alps SKCC series]] switch has been found mounted in several orientations, without affecting keycap fit.

==Alps mount==
[[File:Z_mount.jpg|200px|thumb|Alps-mount keycap and [[Alps SKBM White]] switch]]

A type of mount that is very common for different types of switches. The [[slider]] has a slot that is around 4.6 mm × 2.3 mm at the top; the [[keycap]] has rectangular peg around 4.5 × 2.2 mm.
It is used on various [[:Category:Alps switches|Alps switches]] including the [[Alps SKCL/SKCM series]], and is therefore most often called "Alps mount". The term "Alps mount" does not mean that all Alps switches used this mount: some switches use similar but incompatible mounts, and many more use use totally different mounts. There are more switch types from third parties that use this mount than there are in Alps Electric's entire product range.

Whether there is an industry-wide designation for this type of keycap mount is unknown.

===Switches===
See [[:Category:Keyboard switches with Alps mount|keyboard switches with Alps mount]].
Most notable switches:

*Alps [[Alps SKCL/SKCM series|SKCL/SKCM]] and [[Alps SKBL/SKBM series|SKBL/SKBM]] series
*[[Acer switch]]
*[[SMK Alps mount]] "Monterey"
*[[Omron B3G-S series]]

===Keyboards===
See [[:Category:Keyboards with Alps switches|keyboards with Alps switches]] for keyboards with the Alps and Alps clone switches.

Rubber dome keyboards:

*[[Monterey K208]] (rubber dome keyboard)
*Smartboard rubber dome keyboards
*Some [[AppleDesign Keyboard]]s (rubber dome keyboard)

===Keycap manufacturers and vendors===
Additional keycaps can be purchased from:

*[[Signature Plastics]]
*[[Fentek Industries]]
*[[Tai-Hao]]

{{-}}

==IBM Beam Spring / Selectric mount==
[[File:Beamspring and selectric keycap mount.jpg|thumb|Early IBM Selectric keycap (left), various beam spring keycaps (right).]]

This mount was used for IBM's [[Selectric]] Typewriter and [[beam spring]] switches in the 1960's and 1970's.

===Keyboards===
See [[IBM Beam Spring Keyboards]].










==RAFI mount==
The slider has a cubical top with an edge length of 5&nbsp;mm, underneath of wich are two tiny lugs on opposite sites. The keycap has a mating square hole and recesses where the lugs engage when the keycap is snapped on the slider. RAFI described the mechanism in a patent from 1975, {{cite patent|country=GB|number=1533154}}, but did not put any claims on it.

===Switches===

*All of the [[RAFI Full-Travel Keyswitch|RAFI RS family]]
*[[Siemens STB]]
*[[Sasse 200MN]]
*Low-profile variant of the [[ITW magnetic valve]] switch

===Notes===
First known uses were by [[RAFI]] (1975), [[Siemens]] (1980) and [[Sasse]] (1981); intermarriage is possible at least for some pairings (Siemens on RAFI and vice versa, Siemens on Sasse).

{{-}}

==Mitsumi mount==
[[File:Mitsumi mount.jpg|thumb|200px|Mitsumi mount keycap and tactile [[Mitsumi hybrid switch]]]]

Used for [[Mitsumi hybrid switch]]es and [[Mitsumi mechanical switch]]es. Square peg (keycap) inside a square hole (slider).

{{-}}

==Key Tronic mount==
[[File:Key Tronic foam and foil -- tactile switches.jpg|thumb|200px|Key Tronic [[Key Tronic foam and foil|foam-and-foil switches]]]]
Sliders are cylindrical and hollow with a bar inside. Each keycap has two fingers that snap onto the bar.

Most often these are [[Key Tronic foam and foil]] switches with a rubber sleeve or coiled spring around the slider, but the mount type is also found in keyboards from Alphameric with different switches.<ref name="alphameric">Deskthority thread [http://deskthority.net/keyboards-f2/telex-keyboard-t7741.html#p156487 Telex Keyboard?]. Posted 2014-04-05.</ref>

{{-}}

==Topre mount==
<gallery widths="250" heights="187">
File:Topre_mount_keycaps.jpg|Topre mount, keycaps
</gallery>

==Clare-Pendar mount==
This is a cruciform mount. [[General Instrument Series S950]] differs from [[Alps SKCC Series]] by its use of Clare-Pendar mount keystems. This mount should also cover other Clare-Pendar switch types.

<gallery widths="250" heights="187">
File:General Instrument S95010 -- variants table.jpg    | S95010 (straight)
File:General Instrument S95010 E9 -- variants table.jpg | S95010 E9 (angled)
</gallery>

==Marquardt mount==
Used on Marquardt's electric typewriter switches. The mount provides two plastic prongs, each approximately 1 mm × 2.5 mm in cross section and around 4.9 mm tall, with a 1 mm gap between them.

<gallery widths="250" heights="187">
File:Marquardt butterfly -- keycap mount.jpg | [[Marquardt Butterfly]]
File:Marquardt Olympia custom -- top.jpg     | [[Marquardt Two Fingers Typewriter switch]]
</gallery>

==References==
<references />

[[Category:Keyboard terms]]
[[Category:Keycaps]]