Editing Alps SKCL/SKCM series (section)

==Evolution==
SKCL/SKCM series itself appears to a [[DIN standard]] re-imagining of the earlier [[Alps SKCC series]]. The "switchplate" contact assembly was lifted wholesale from the earlier switch; the important changes were repositioning the mounting plate to be much lower down the switch body, and a new slider design that allowed the mounting stem within the keycap to pass inside the switch. While SKCC and SKCL/SKCM are around the same size as each other, these changes permitted a substantial reduction in keyboard profile without altering the switching operation in any way. The redesigned shell also brought with it a different approach to illumination, placing the LED inside the switch instead of supported above it on coil springs.

The exact design goals are currently unknown. The new shell left space to introduce a [[click leaf]] in place of the LED. Because the slits in the tactile switch shell are shorter than the slits of the linear switch, it would seem that this was an afterthought; later linear switches adopted the shorter slits when the shells were retooled at the end of the 1980s. The early history remains speculation, due to a lack of documentation and very limited dating evidence.

The SKCL/SKCM design was modified numerous times by Alps over its lifetime. This process remains poorly understood, but a number of changes have been noted. Some of these points are expanded further under Design, below.

Terminal sealant has been found in one instance.<ref>Deskthority — [https://deskthority.net/keyboards-f2/alps-appreciation-t12915-1260.html#p352622 Alps Appreciation] (post 352622)</ref>

*The original SKCL shell from ca. 1983 used longer, potentially more fragile tabs between the slits, and black switchplates
*When SKCM was introduced shortly afterwards, the new non-LED shell used shorter slits
*Around 1984 or so, the switchplate colour changed from black to grey
*Around 1989, all the slider colours changed, with the suggestion being that a newer, smoother plastic was used (this can be seen in the shinier sliders of switches from this point onwards and the lack of dry lubricant on switches from this period onwards); this was not a clean break, as [[Alps SKCM White|SKCM White]] continued to use dry lubricant briefly after it replaced [[Alps SKCM Blue|SKCM Blue]],<ref name="DT-dry_lubricant" /> and uncertainty remains as to which older switches correspond to which newer switches
*The 1989–1990 overhaul also saw the introduction of top branding on switches—using the newer Alps logo—and SKCL switches changed over to the shorter tabs between the slits when the shells were retooled (noticeable in comparison between typical SKCL Green and typical SKCL Yellow)
*Other changes during the 1989–1990 overhaul included switchplate alterations, first to colourless plastic, and then to a shorter version; as with the other changes, these occurred in a series of transitions
*Some switches around the end of the 80s had dark grey-blue upper shells instead of black; the timeframe for this remains uncertain, but SKCM Orange, White and Ivory are known to be amongst those affected
*Around 1993, the slits were removed entirely

===Generations===
Very broadly speaking, the series can be thought of as having three generations:

;First generation
:1983–1989; original colours, no top branding, long switchplates and dry lubricant applied to the sliders in at least some instances (first pine generation)
;Second generation
:1989–1993; replacement colours, top branding, short switchplates and potentially a change in slider plastic to remove the need for dry lubricant (second pine generation)
;Third generation
:1993–1996; removal of slits (bamboo generation)

The changes to the switches between the first and second generations did not occur collectively but progressively; combinations different from the above exist from within the transition period. The specifics of the changes around 1993 that led to MouseFan rating them lower ("bamboo" vs "pine") are not well understood.