A datacenter rack for vertically stacking a plurality of electronic devices is provided. The rack has a frame assembly having two vertical support components and a plurality of removeable trays configured to be inserted between and supported by the vertical support components. Each tray has a pair of opposing sides extending parallel to a longitudinal axis and each of the pair of opposing sides has a tensioned adjustment mechanism to shorten a length of each side to compress the tray in the longitudinal axis, with the tensioned adjustment mechanisms providing a tensioning force against the compression. Each tray also has a top surface with a movement facilitating arrangement for facilitating movement of an electronic device along the tray in the longitudinal axis.