Abstract: A method of micro machining a workpiece; a micro machining apparatus and a micro machined workpiece. The method includes the steps of laser cutting a test bore in a test piece using a laser beam; measuring the test bore using either a measurement probe or an electrode; correlating the electrode to the laser beam; laser ablating the surface the workpiece in a first region; and electrical discharge machining the workpiece in the first region to produce at least one bore in the workpiece. The workpiece has a surface coating and at least one bore, wherein the bore passes through the surface coating with a diameter that is within 0.3 mm of the diameter of the bore in the remainder of the workpiece.

Abstract: A method for fabricating a quadrupole mass filter (QMF) or quadrupole ion trap (QIT) capable of generating a hyperbolic electric field. The method comprises: (a) cutting four elongate erodible metal workpieces axially at opposing extremities; (b) parallel mounting the four elongate erodible metal workpieces axially in an elongate slot in an insulating housing in a mutually spaced apart disposition such that an axial bore is formed therebetween whereby a first part of each elongate erodible metal workpiece is freely inward facing and the cutting forms a recess remote from the axis of the insulating housing; (c) electrically connecting the erodible metal workpieces; and (d) generating electrical discharges between the erodible metal workpiece and a wire electrode as the wire electrode passes through the axial bore to erode the erodible metal of the first part of the erodible metal workpiece to a hyperbolic profile.

Abstract: The present invention relates to a method for fabricating a quadrupole mass filter (QMF) or a quadrupole ion trap (QIT).

Abstract: In an electrical discharge machining apparatus having a nose guide (12) and an electrode datum (26) movable relative to one another, a cartridge (14) movable relative to the nose guide, a plurality of substantially parallel electrodes (16) supported by the nose guide (12) and the cartridge (14) and a cartridge clamp (32) engageable to prevent relative motion between the electrodes (16) and the cartridge (14), a method of refeeding and realigning the electrodes between machining operations compensates for erosion. In this method, the separation of the datum (26) from the nose guide (12) and cartridge (14) is decreased while protruding electrodes that engage the datum are received back into the cartridge. Because the nose guide and cartridge remain in fixed relation at that stage there is no need for a friction pad between the cartridge (14) and the electrodes (16). The electrode datum may be a surface of the workpiece that is to be machined.