Does anyone know of a good reference for how to design the sorts of linear rail systems you find in printers and cd-rom drives? I'm looking for something simple and cheap to manufacture, but is still very precise as long as it isn't subjected to large loads. Information about how to design the preloading elements, when to use teflon, uhmw, or sintered bronze, how much preload, these sorts of things. Or is it just that this sort of expertise is usually passed around within companies?