A turbo-molecular vacuum pump comprising: a housing for accommodating rotor and stator components of the turbo-molecular vacuum pump having an inlet side and an outlet side , a drive shaft coupled to the rotor components for driving the rotor components around a longitudinal axis , bearing means for coupling the drive shaft to the housing and to allow relative rotary movement thereof, and a spacer for locating and coupling the stator components relative to the housing; wherein each of said stator components comprises a series of stator blades extending radially from the longitudinal axis and between an inner portion to an outer portion, each of the stator blades being angled with respect to a plane defined by the inner portion, wherein the outer portion of at least one of the stator components comprises a resilient portion arranged to cooperate with the spacer, said resilient portion comprising a compliant outer tip section disposed at the ends of the stator blades, said tip section integrally formed with and extending an end of the stator blade, wherein a stator stack comprises a plurality of spacers each being interposed between adjacent stator components and, when located in the pump housing, a securing means secures the stator stack in a position and compresses the respective resilient portions; and wherein said resilient portion is configured to apply a spring load when under compression between adjacent spacers such that the stator component is held in place during pump manufacture and operation; and said spacers are provided with stops in the form of an external, predefined gap between adjacent spacers when a stator blade tip is disposed between the spacers; and said gap , when closed under compression by the securing means, causes said stator blades to have become compressed by said predetermined gap to prevent over-compression of the stator blade tips. a housing for accommodating rotor and stator components of the turbo-molecular vacuum pump having an inlet side and an outlet side , a drive shaft coupled to the rotor components for driving the rotor components around a longitudinal axis , bearing means for coupling the drive shaft to the housing and to allow relative rotary movement thereof, and a spacer for locating and coupling the stator components relative to the housing; wherein each of said stator components comprises a series of stator blades extending radially from the longitudinal axis and between an inner portion to an outer portion, each of the stator blades being angled with respect to a plane defined by the inner portion, wherein the outer portion of at least one of the stator components comprises a resilient portion arranged to cooperate with the spacer, said resilient portion comprising a compliant outer tip section disposed at the ends of the stator blades, said tip section integrally formed with and extending an end of the stator blade, wherein a stator stack comprises a plurality of spacers each being interposed between adjacent stator components and, when located in the pump housing, a securing means secures the stator stack in a position and compresses the respective resilient portions; and wherein said resilient portion is configured to apply a spring load when under compression between adjacent spacers such that the stator component is held in place during pump manufacture and operation; and said spacers are provided with stops in the form of an external, predefined gap between adjacent spacers when a stator blade tip is disposed between the spacers; and said gap , when closed under compression by the securing means, causes said stator blades to have become compressed by said predetermined gap to prevent over-compression of the stator blade tips. <EOS>