ASCII Illustrations of the keyswitch mechanism.

Key stem, top and side view ( circles are hard :( )

       Top view       Side profile
       
       _,x^^x,_       
      x^      ^x      ▊         ▊
     x          x     ▊         ▊
     x          x     ▊    ┏┓   ▊
      x        x
       `'x,,x'`

Spring guide (box channel with horizontal stopper strip)

       Top view       Side profile
       
      ━━━┳━━┳━━━          ███
         ┃  ┃             ███
         ┗━━┛            ▄███

Guide assembly inside stem

       Top view       Side profile
       
       _,x^^x,_    
      x^      ^x       ▊      ███▊
     x          x      ▊      ███▊
    ━x━━━┳━━┳━━━x━     ▊     ▅███▊
      x  ┃  ┃  x
       `x┗━━┛x`
         `^^` 

Outer key guide

     ▊    ┏━┓    ▊
     ▊    ┃ ┃    ▊
     ▊    ┃ ┃    ▊
    ▅▊    ┃ ┃    ▊

Key assembly stem inside key guide

      ▊      ███▊
     ▊▊    ┏━┓██▊▊
     ▊▊    ┃▅┃██▊▊
     ▊     ┃ ┃   ▊
    ▅▊     ┃ ┃   ▊

Key stem with key cap glued

  ███████████████████
      ▊      ███▊    
     ▊▊    ┏━┓██▊▊
     ▊▊    ┃▅┃██▊▊
     ▊     ┃ ┃   ▊
    ▅▊     ┃ ┃   ▊

Key asembly with spring inserted

  ███████████████████
      ▊      ███▊     
      ▊      ███▊ 
     ▊▊    ┏▅┓██▊▊
     ▊     ┃ ┃ @ ▊
     ▊     ┃ ┃ @ ▊
    ▅▊     ┃ ┃ @ ▊

Key pressed

  ███████████████████
     ▊▊    ┏━┓██▊▊   
     ▊▊    ┃ ┃██▊▊
     ▊▊    ┃▅┃██▊▊ 
    ▅▊     ┃ ┃ &@▊

Key switches installed on base sheet

                                 Pressed key
██████  ███████████████████                       ███████████████████
█▊          ▊      ███▊                               ▊      ███▊
█▊          ▊      ███▊      ███████████████████      ▊      ███▊
█▊▊        ▊▊    ┏▅┓██▊▊        ▊▊    ┏━┓██▊▊        ▊▊    ┏▅┓██▊▊
@ ▊        ▊     ┃ ┃ @ ▊        ▊▊    ┃ ┃██▊▊        ▊     ┃ ┃ @ ▊
@ ▊        ▊     ┃ ┃ @ ▊        ▊▊    ┃▅┃██▊▊        ▊     ┃ ┃ @ ▊
@ ▊████████▊     ┃ ┃ @ ▊████████▊     ┃ ┃ &@▊████████▊     ┃ ┃ @ ▊███