Cubix, 3131 29 bytes
uo.['.']@;uo@[)o'U);!A?Uo;o;o;osro;o;o;os:'/.uru:''
A
can also be substituted for i
; trying to figure out if there's a good waytrying to figure out if there's a good way to squeeze another byte or two out of this. -2 bytes thanks to squeeze another byte or two out of this.MickyT! Also outgolfed by MickyT!
Fits on a 3x3x3 cube:
u o .@
[ ') .o
' ]U @)
; ! A ? Ur o ; o ; o ; o
s : ' / . u r : ' ' . . . .
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